【初三英语试题精选】2018年中考数学阅读理解专题复习题(人教版含答案)
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2018年全国有关中考数学试题分类汇编(阅读理解题)及解析一、选择题1、 (2007四川眉山)为确保信息安全, 信息需加密传翰,发送方将明文加密为密文传输给接收方, 接收方收到密文后解密还原为明文. 己知某种加密规则为:明文a 、b 对应的密文为2a — b 、2a + b.例如,明文1、2对应的密文是一3、4.当接收方收到密文是 1、7时,解密得到的明文是( ).C A .— 1, 1 B . 1, 3 C . 3, ID . 1, I2、 ( 2007湖南长沙)在密码学中,直接可以看到内容为明码,对明码进行某种处理后得到的内容 为密码.有一种密码,将英文26个字母a, b, C ,…,Z (不论大小写)依次对应 1, 2, 3,…,X 126这26个自然数(见表格)•当明码对应的序号X 为奇数时,密码对应的序号 y;当明码2对应的序号X 为偶数时,密码对应的序号 y - 13 .A . gawqB . shxcC . sdriD . love 二、填空题6x 3 0的两实数根,贝U 翌 凶的值为X 1x 22、( 2007四川巴中)先阅读下列材料,然后解答问题:从A, B , C 三张卡片中选两张,有三种不同选法,抽象成数学问题就是从 3个元素中选取2个元素组合,记作C ; 口 3.2 1一般地,从m 个元素中选取n 个元素组合,记作:C :m (m 1儿(m n °n (n 1)L 3 2 17 6 5 4 3例:从7个元素中选5个元素,共有C 5321种不同的选法.5 4 3 2 1问题:从某学习小组 10人中选取3人参加活动,不同的选法共有 _种.120a b3、( 2007广东梅州)将4个数a, b, c, d 排成2行、2列,两边各加一条竖直线记成c d1、( 2007四川德阳)阅读材料:设一元二次方程 2ax bx c 0的两根为X 1, X 2,则两根与方程系数之间有如下关系: x 1 x 2-,X 1gx 2 C .根据该材料填空: a a已知X 1 , x 2是方程x 210定义ad bc ,上述记号就叫做2阶行列式.若6,则x答: .2三、解答题1、( 2007浙江临安)阅读下列题目的解题过程:已知a 、b 、c 为 的三边,且满足解:c 2(a 2 b 2) (a 2 b 2)(a 2 b 2) (B )c 2 a 2 b 2(C )ABC 是直角三角形问:(1) 上述解题过程,从哪一步开始出现错误?请写出该步的代号:______________(2 )错误的原因为: ___________________________________________________________(3)本题正确的结论为: _____________ . 解:(1) C ---------------------- 2 分 (2)没有考虑a 2 b 20 ------- 4分(3) ABC 是直角三角形或等腰三角形 --- 6分 2、( 2007云南双柏)阅读下列材料,并解决后面的问题.材料:一般地,n 个相同的因数a 相乘:a a a 记为a n .如23= 8,此时,3叫做以2为底8n 个的对数,记为log 2 8即log 2 8 3 .一般地,若a n b a 0且a 1,b 0 ,贝U n 叫做以a 为底b 的对数,记为log a b 即log a b n •如34 81,则4叫做以3为底81的对数,记为log 3 81 (即卩log 3 81 4).问题:(1)计算以下各 对数的值:(3分)log 2 4 log 216 log 2 64.(2) 观察(1)中三数4、16、64之间满足怎样的关系式?log 2 4、log 216 > log 2 64之间又满足怎样的关系式? ( 2分)(3) 由(2)的结果,你能归纳出一个一般性的结论吗?(2分)log a M logN __________ a 0且a 1,M 0, N 0(4) 根据幕的运算法则:a n a m a n m 以及对数的含义证明上述结论.(3分)证明:解:(1) log 2 4 2 , log 216 4 , log 2 64 6,log 2 4 + log 216 = log 2 64(3) log a M + log a N = log a (MN),试判断的形状.(2) 4X 16= 64•••从A 点到B 点并禁止经过 C 点的走法数为35- 18= 17种. 10分⑶P(顺利开车到达B 点)=1735则 abiM , a b2 N••• MN a b ia b2a b ib2二 b i + b 2= log a (MN ) 即 log a M + log a N = log a (MN )3、( 2007安徽芜湖)阅读以下材料,并解答以下问题. 完成一件事有两类不同的方案,在第一类方案中有 m 种不同的方法,在第二类方案中有n 种不同的方法•那么完成这件事共有N = m + n 种不同的方法,这是分类加法计数原理;完成一件事需要两个步骤,做第一步有 m 种不同的方法,做第二步有 n 种不同的方法.那么完成这件事共有 N =mxn 种不同的方法,这就是分步乘法计数原理.”如完成沿图1所示的街道从 A 点出发向B 点行进这件事(规定必须向北走,…或向东走,.…),会有多种不同的走法,其中从 A 点出发到某些交叉点 的走法数已在图2填出.(1)根据以上原理和图2 的提示, 算出从A 出发到达其余交叉点的走法数,将数字填入图 2的空圆中,并回答从 A 点出发到B 点的走法共有多少种?种........................... 5 分(1)方法一:可先求从A 点到B 点,并经过交叉点C 的走法数,再用从A 点到B 点总走法数减去 它,即得从A 点到B 点,但不经过交叉点 C 的走法数.完成从A 点出发经C 点到B 点这件事可分两步,先从 A 点到C 点,再从C 点到B 点.使用分类 加法计数原理,算出从 A 点到C 点的走法是3种,见图2;算出从C 点到B 点的走法为6种,见 图3,再运用分步乘法计数原理,得到从A 点经C 点到B 点的走法有3X6= 18种.•••从A 点到B 点但不经过 C 点的走法数为35- 18= 17种.方法二:由于交叉点C 道路施工,禁止通行,故视为相邻道路不通, 可删除与C 点紧相连的线段.运 用分类加法计数原理,算出从 A 点到B 点并禁止通过交叉点 C 的走法有17种.从A 点到各交叉 点的走法数见图4.(4)证明:设 log a M = b ilog a N = b 2(2)运用适当的原理和方法算出从 A 点出发到达B 点,并禁止通过交叉点C 的走法有多少种?(3)现由于交叉点 C 道路施工,禁止通行.求如任选一种走法,点(无返回)概率是多少?解: 解:(1):完 或向东走,••倒达A 点以外 与其相邻的南 之和.故使用分类加 到达其余各交 答:从A 点到B从 A 点出发能顺利开车到达 B成从A 点到B 点必须向北走,的任意交叉点的走法数只能是 10分法计数原理,由此算出从 A 点叉点的走法数,填表如图 1, 点的走法共有 3517答:任选一种走法,顺利开车到达B点的概率是17•35一AC BC4、(2007江苏连云港)如图1,点C将线段AB分成两部分,如果,那么称点AB AC线段AB的黄金分割点.某研究小组在进行课题学习时,由黄金分割点联想到“黄金分割线”,类似地给出“黄金分割线” 的定义:直线I将一个面积为S的图形分成两部分,这两部分的面积分别为S, , S2,如果§S那么称直线I为该图形的黄金分割线.(1)研究小组猜想:在厶ABC中,若点D为AB边上的黄金分割点(如图2),则直线CD是厶ABC 的黄金分割线•你认为对吗?为什么?(2)请你说明:三角形的中线是否也是该三角形的黄金分割线?(3)研究小组在进一步探究中发现:过点C任作一条直线交AB于点E,再过点D作直线DF // CE,交AC于点F ,连接EF (如图3),则直线EF也是△ ABC 的黄金分割线.请你说明理由.(4)如图4,点E是丫ABCD的边AB的黄金分割点,过点E作EF // AD,交DC于点F,显然直线EF是Y ABCD的黄金分割线.请你画一条Y ABCD的黄金分割线,使它不经过Y ABCD 各边黄金分割点.解:(1)直线CD是厶ABC的黄金分割线•理由如下:设厶ABC的边AB上的高为h •1 1SA ADC—AD 6, S A BDC—BD 6 ,2 2所以S A ADC AD S A BDC BDS AABCAB S A ADC AD(2) 因为三角形的中线将三角形分成面积相等的两部分,此时Si s2-—,所以三角形的中线不可能是该三角形的黄金分割线.s q(3)因为DF // CE ,所以△ DEC和△ FCE的公共边CE上的高也相等,所以有S A DEC S A FCE•设直线EF与CD交于点G •所以S A DGE S A FGC •12分S2S i1S A ABC 2ABgh,又因为点D为边AB的黄金分割点,所以有A2■BD•因此AB AD S A ABCS A BDCS AADC所以,直线CD是厶ABC的黄金分割线. ...............1S| S2-所以S A ADC S四边形AFGD S A FGC因此,直线EF 也是△ ABC 的黄金分割线. ............................. 10分 (4)画法不惟一,现提供两种画法; ............................... 12分画法一:如答图1,取EF 的中点G ,再过点G 作一条直线分别交 AB ,DC 于M , N 点,则直线 MN 就是Y ABCD 的黄金分割线.画法二:如答图2,在DF 上取一点N ,连接EN ,再过点F 作FM 连接MN ,则直线MN 就是Y ABCD 的黄金分割线.5、( 2007浙江衢州)请阅读下列材料:问题:如图(2),一圆柱的底面半径为 5dm , BC 是底面直径,求一只蚂蚁从 A 点出发沿圆柱表面 爬行到点C 的最短路线•小明设计了两条路线: 路线1:侧面展开图中的先端 AC •如下图(2)所示: 设路线1的长度为11,则l 12路线2:高线AB +底面直径2设路线2的长度为12,则丨22 211 丨225 25 2252 2• •丨1 1 2 丨1 l 2所以要选择路线2较短.(1)小明对上述结论有些疑惑,于是他把条件改成:“圆柱的底面半径为 继续按前面的路线进行计算•请你帮小明完成下面的计算: 所以应选择路线 ____________ (填1或2)较短.(2)请你帮小明继续研究:在一般情况下,当圆柱的底面半径为 r ,高为h 时,应如何选择上面的两条路线才能使蚂蚁从点 A 出发沿圆柱表面爬行到 C 点的路线最短. 解:(1) lj AC 2 AB 2 AC 252225l 22 (AB AC)2(5 2)249又因为S^ ADCS A ABCS A BDC SA ADC,所以SA AEFABCS四边形BEFCSA AEF// NE 交AB 于点M ,AC 2 AB 2BC .如上图(2(AB AC) 25 2200AC 2 521)所示:2(5 10) 25( 28)路线1: l 12 AC 2;路线2: l 22(AB AC)2.2一 2•-11ll 1I 2 (填〉或v )(第4题答图1) (第4题答图2)1dm ,高AB 为成dm ”l22所以要选择路线1较短.AC 2 AB 22 2AC h (r)2122 (AB AC)2 (h 2r)2 Qlj l 22 h 2 ( r)2 (h 2r)2 = r( 2r 4r 4h) = r[( 24)r 4h]4h 2~时,l 12 I 22; 当 r 4 6、( 2007甘肃白银等3市)阅读下边 方法一:教材中方法2Q ax2Q 配方可a(xa((X bx c o,2rb 得:c)2 o|o 4ac kb ?2a c b <°,40b __ ) __ —2 2O ))2 b4a 4ac ,… b ^a. c b 2o o 4a c ” bba 4a Sac 时,lj > I 22;当 r v4兀二次方程求根公式的两种推导方法:方法二:•/ ax 2 + bx + c = 0,• 4a 2x 2 + 4abx + 4ac = 0, • (2ax + b)2= b 2 — 4ac . 当 b 2 — 4ac >0时,4h时,h 2 v I 22. 42b 22ax + b = ±. b 24ac , ••• 2ax =— b ±. b 24ac . b Vb 24ac…x =2a x bb 2a°24a4ac 请回答下列问题2a b 4a 24ac , (1) 两种方法有什么异4同?你认为哪个方法好?(2) x 说说你有什么感想竺 解:(1)都采用配方法2a 方法一是将二次项的系数化为 式•方法一较好. 7、( 2007江苏无锡)图1是由若干个小圆圈堆成的一个形如正三角形的图案,最上面一层有一个 圆圈,以下各层均比上一层多一个圆圈,一共堆了 n 层•将图1倒置后与原图1拼成图2的形状, 这样我们可以算出图1中所有圆圈的个数为1 2 3 L n 世 B . 2 1,方法二是将二次项系数变成一个平方 第“层 ■ 4 * 00—0000—00图1 中的圆圈共有12层, 如果图1 正整数1,2,3,4 ,L ,则最底层最左边这个圆圈中的数是 都按图4的方式填上一串连续的整数 之和.解:(1) 67. ................................... 图2 图3 (1)我们自上往下,在每个圆圈中都按图 3的方式填上一串连续的 _; ( 2)我们自上往下,在每个圆圈中 23, 22 , 21, L ,求图4中所有圆圈中各数的绝对值 (2)图4中所有圆圈中共有12 3 L 12咚378个数,2其中23个负数,1个0, 54个正数, 图4中所有圆圈中各数的绝对值之和| 23| | 22| L | 1| 0 1 2 L 54(1 2 3 L 23) (1 2 3 L 54) 276 1485 1761 .8、( 2007鄂尔多斯)我们给出如下定义:若一个四边形中存在相邻两边的平方和等于一条对角线的平方,则称这个四边形为勾股四边形,这两条相邻的边称为这个四边形的勾股边.(1)写出你所学过的特殊四边形中是勾股四边形的两种图形的名称 _________ ,________ ;(2)如图16 (1),已知格点(小正方形的顶点)0(0,0) , A(3,0) , B(0,4),请你画出以格点为顶点,OA, OB为勾股边且对角线相等的勾股四边形OAMB ;(3)如图16 (2),将△ABC绕顶点B按顺时针方向旋转60°,得到△DBE,连结AD, DC ,Z DCB 30°•DC 2 BC 2 AC 2,即四边形 ABCD 是勾股四边形求证:DC 2 BC 2 AC 2,即四边形ABCD 是勾股四边形.解:(1) 正方形、长方形、(2) 答案如图所示. fy (3)证明: Q Z CBE 连结EC M .........(填正确一个得1分) 鹫形正确得 1分):Z BCE 60Q Z DCB O o 」 22 2 90o *DC EC DE xC直角梯形•(任选两个均可) 图'16 ■(2) M (3,4)或 M(4,3) •(没有60•A 分(根据图形给分, AC D。
2018年中考英语阅读理解练习题及答案mails within a minuteGiving all kinds of information is probably the biggest advantage of the Inter We can use search engines to find the information we need Just type in a keyword or keywords and the search engine will give us a list of suitable websites to look atWe can enjoy a lot on the Inter by downloading games, visiting chat rooms or surfing (浏览)websites There are some games for free We can meet neand interesting people in the chat noe can also listen to musicand see filmsNo,there is a lot of service on the Inter such as online banking ,job finding and ticket buying We canalso do shopping and find nearly all kinds of goods Sometimes we can find something that is quite good but very cheap26Homany main advantages of the Inter are talked about in the passage?A ThreeB FourC FiveD Six27What fact doesn’t the passage provide?A We can find almost anything we want to knoon the InterB Some games on the Inter are freeC We can buy most things we need on the InterD Goods on the Inter are more expensive than those in real shops28Which title best gives the main idea of the passage?A Online Shopping。
2018年中考英语复习应用文阅读理解题(附答案)west of the museum D.north-east of the post office 50.Start from A,walk along Adam Street.turn left at the second crossing,and she will find ________.A.the park on the left B.the cinema on the rightC.the library on the left D.the bookshop on the right (7)Bayfield shopping Coupons Bayfield 购物券61 If you spend 100 dollars or more, you canA get a CD freeB get 6 hours of free parkingC get some stamps free62 Buy one tie at Daniel’s Menswear, you may get another freeA cheaper tieB more expensive tieC tie of the same price63 You can get a 10% discount on any books if you at the Book StoreA buy some giftsB buy some ticketsC shothis coupon64 If you want to have free soft drink, you can go toA Mike’s CaféB The Book StoreC Daniel’s Menswear65 If John pays 10 dollars for a full-pr ice movie ticket on Tuesdays;he can buy a second ticket for onlyA 5 dollarsB 10 dollarsC 15 dollars(8)Hong Kong Harbor Cruise By NightEnjoy your wonderful dinner on the ferry and see the fantastic city lightsTIME 700 pm 1000 pm dailyPRICE With dinner Without dinnerAdult HK$300 HK$1be Japanese bank robber asked workers in the bank hohe could carry out the robbery.The man is 58 years old.Newspapers said that the man first asked a bank teller,“Any idea about hoI rob a bank?” 68 “He left quietly when asked to,”the police spokesman said.“But he hurt himself in the leg with a knife that he carried.”◆ 69 It changes its color from blue to white as the food temperature reaches 150.DBACC(7)61-65 BCCAA(8)66-70 ABCBC(9)59-62.CADB(10)67-70.BBAC。
2018九年级中考英语真题试卷试卷I(选择题共70分)(一)听力部分(共25分)一、听力(本题有15小题,第一节每小题1分,第二、三节每小题2分,共计25分)第一节:听小对话,回答问题1. How's the weather now?A. RainyB. FineC. Windy2. When was the woman speaker born?A. In FebruaryB. In MarchC. In April3. What's Laura doing?A. WorkingB. Playing soccerC. Reading4. What kind of clothes will Sandy wear?A. A white shirtB. A black dressC. A white coat5. Who is the woman probably speaking to?A. A driverB. An artistC. A doctor第二节:听较长对话,回答问题听下面一段对话,回答第6-7小题6. How much will the man pay?A.$6B.$16C.$267. Where does the conversation probably take place?A. In a post officeB,In a zoo C. In a bank听下面一段对话,回答第8—10小题。
8. Where did Carla go last night?A. To her friend's houseB. To her cousin's houseC. To her mom's house9. How did Carla like chicken?A. She couldn’t stand itB. She didn’t mind itC. She enjoyed it a lot10. What food came out at last?A. A tomato pieB. A chocolate pieC. An apple pie第三节:听独白,回答问题11. Whose birthday is it next month?A. Kelly’s dad’sB. Kelly’sC. Kelly's mum’s12. How are Kelly’s family going to London?A. By planeB. By trainC. By subway13. Why do Kelly’s family plan to walk to the Design Museum from the hotel?A. Because they want to take exerciseB. Because the hotel is near the museumC. Because they want to see the sights around14. What are Kelly's family going to do this Saturday?A. To visit Big BenB. To go shoppingC. To play in the park.15. How does Kelly probably feel about the coming vacation?A. It'll be terribleB. It'll be dullC. It’ll be exciting(二)笔试部分(共45分)二、完形填空(本题有15小题,每小题1分,共计15分)阅读下面短文,然后从各题所给的四个项中选出一个最佳答案My son Daniel began surfing at the age of 13. After school each day he put on hiswet suit and waited to be challenged by three-to-six-foot waves. Daniels love for theride was tested one 16 afternoon.“ Your son's been in an accident,” the lifeguard(生员)reported to my 17 Mikeover the phone hurriedly. “18 he came up to the top of the water, the point of the boardwas headed toward his eye.”Mike rushed our son to the hospital. He 19 26 stitches(缝全)from the corner of his eye to the bridge of his noseI was 20 home from a meeting while Daniels eye was being stitched. Mike drove 21 to the airport after they left the doctors office. He greeted 22 at the gate while Daniel was waiting in the car. Daniel?"I questioned. I remember thinking the 23 must have been terrible that day.“He’s been in an accident,but he’s going to be fin e. "Mike comforted me.I ran to the car. My son reached out both arms,crying,Oh,Mom,I’m so glad you re home.1 sobbed(抽泣)in his arms,telling him how24 I felt about not being there when the lifeguard called.“It's okay,Mom,”he said. “I'll be fine. The doctor said can go back in the water in eight days.” Was he 25 I wanted to tell him that he wasn’t allowed to go near water again until he was 35,but 26I controlled myselfHe kept asking me to let him go back on the 27 for the next seven days. One day after I 28“ No”to him for the 100th time,he beat me at my own game.“ Mom,you taught us never to 29 what we love.”I gave in. Back then Daniel was just a boy with deep 30 for surfing. Now he is among the top 25 surfers in the world.16. A. unusual B. boring C. amazing D. relaxing17. A. brother B. uncle C. husband D. father18. A. If B. When C. Unless D. Though19. A. avoided B. changed C. received D. discovered20. A. flying B. driving C. boating D. walking21. A. suddenly B. happily C. comfortably D. directly22. A. her B. them C. us D. me23. A. waves B. dreams C. clouds D. suggestions24. A. brave B. lucky C. awful D. proud25. A. busy B. crazy C. friendly D. polite26. A. instead B. already C. even D. often27. A. plane B. bed C. board D. chair28. A. posted B. offered C. threw D. repeated29. A. find out B. give up C. hand out D. pick up30. A. love B. fear C. sadness D. regret三、阅读理解(本题有15小题,每小题2分,共计30分)阅读下面四篇材料,然后从各题所给的四个选项中选出一个最佳答案。
2018中考英语阅读理解题及答案10篇-your real name, home address, age, school, phone number or other personal informationCheck with your parents before giving out a credit (信用) card numberNever send a photo of yourself to someone in e-mail unless your parents say it’s OKCheck with your parents before going into a chat room Different chat rooms have different rules and attract different kinds of people You and your parents must make sure it’s a right place for youNever agree to meet someone you met on the Inter without your parent’s permission (允许) Never meet anyone you met on line aloneAlways remember that people online may not be who they say they are Treat everyone online as strangersIf something you see or read online makes you unfortable, leave the site Tell a parent or teacher right away Treat other people as you’d like to be treated Never use bad languageRemember—not everything you read on the Inter is true ( )1 If you want a true friend on the Inter , you can ____________A tell the people what your name isB meet the people on line aloneC write an e-mail about yourselfD get your parent’s permission( )2 It’s good for children to ________ on the InterA give password to othersB get useful knowledge and。
2018年中考英语阅读复习题(含答案) COM six of them died]The researchers said the doctors’ study provides clear proof that taking aspirin can prevent a first hea rt attack in healthy, older men They said, however, the result does not mean every man over the age of fifty should take aspirin They said aspirin couldn’t help men who do not eat healthy foods, who smoke cigarettes and who are fat The researchers said men who think they would be helped by taking aspirin should talk with their doctors first1 The passage tells us that the neuse of aspirin is ______Ato treat heart disease B to reduce pain while one suffers from a heart attackC to help old people to be more healthyD to reduce the chance of a heart attack in old men2 Aspirin can help those who ______A work as doctorsB are under 40 years oldC are fat and smoke cigarettesD are older and healthy3 At last the researchers advised us to take aspirin ______A with careB as much as we likeC every dayD only considering the age4 Fro m the experiment we can conclude that about _____ of people who suffered from heart attacks without aspirin diedA 7%B 11%C 19%D 44%【答案与解析】本介绍了科学家对阿斯匹林的研究成果。
题型三阅读理解专项训练一人物故事时间:8~10分钟/篇分值:2分/小题Passage 1(2018黄冈)One day, Mr. Li was reading a book in his office after school. To his surprise, a ball flew in suddenly and hurt him on the head. He took the ball to the window, but he only saw a group of boy students running away quickly and disappearing in a minute. He sat down again and continued his reading. As it got dark, it was time for him to leave for home. Looking at the ball, he wondered what to do with it. He knew the owner of the ball must be nearby and wished to get it back. He went downstairs and walked to the playground. It was at the center of the playground that he placed the ball with a piece of paper, on which he wrote “Be careful next time!”. Then he walked away.The next morning, as Mr. Li opened the office door, he found the same piece of paper on the floor. Some words were added after his words: “Thank you for your kindness. Anyway, you are a clever fellow.”( )1. What happened while Mr. Li was reading in his office?A. The window was broken by a ball.B. A ball hurt him on the head.C. A ball hit the window.D. The door was broken by a ball.( )2. Why did the owner of the ball run away quickly?A. He was afraid of Mr. Li.B. He wanted to get the ball back.C. He wanted to go home.D. He went to look for the ball.( )3. How did Mr. Li deal with the ball?A. He took it home.B. He put it in his office.C. He put it back on the playground.D. He had no idea about it.( )4. According to the passage, we can know that ________.A. Mr. Li is interested in readingB. Mr. Li is too hard on his studentsC. Mr. Li is good at playing sportsD. Mr. Li is a clever teacher with kindnessPassage 2(2018安徽)While many young people were enjoying the summer vacation, Zach Bonner was working his hardest. Zach started walking from Valrico, Florida, his hometown, on Christmas, 2009. He reached Los Angeles nine months later in September, 2010. He covered a total of 2,478 miles and raised $120,000 for kids in need. Along the way, Zach attended school online. His mother, brother and sister took turns to walk or drive together with him.Although he is very young, Zach has a long history of helping others. When a terrible storm hit town in 2004, Zach, when six, pulled a wagon(小推车)through his community and collected food for people in need.He has raised $400,000 for his Little Red Wagon Foundation since then. It gives money to projects which help homeless children. In 2007, Zach began walking to support a children's charity(慈善组织)in Tampa, Florida. He finished his journey 23 days later, 280 miles away in Tallahassee. Then in the summer of 2009, he trekked about 670 miles from Atlanta to Washington, D.C., in just two months.“As long as there are homeless kids, I will never stop walking for them.” Zach says.( )1. What did Zach do during the summer vacation in 2010?A. He stayed at home to look after his family.B. He travelled to his hometown with his family.C. He joined in a school activity with other kids.D. He walked to collect money for kids in need.( )2. We can learn from Paragraph 2 that Zach________.A. began to help people at a very early ageB. made money to pay for his educationC. enjoyed playing around in his communityD. worked very hard for his family( )3. At what age did Zach start walking to support a Tampa children's charity?A. At six.B. At nine.C. At eleven.D. At twelve.()4. The underlined word “trekked”in Paragraph 3 probably means “________”.A. 延伸B. 挖掘C. 跋涉D. 飞行( )5. Which of the following best describes Zach?A. Friendly and shy.B. Silly but lovely.C. Kind and helpful.D. Clever but lazy.Passage 3(2018 北京)From Nobody to SomebodyBrian was a funny student. He loved watching comedies(喜剧)best and hoped to become a comedy actor one day.When he heard about the talent show to be held at his school, Brian decided to take part in. He had never acted on stage(舞台)before, and he was very excited. But some students laughed at him. “You are not funny but silly,” Ken, one of his classmates, said to his face. “No one will like what you do,” another boy also said to him, loudly.Brian couldn't understand why they were so unkind to him. For a moment, he thoughtabout giving up the show. But he remembered how much his friends liked his jokes, and also his teachers said he was very funny. So he decided to prepare for the show.Brian did a great job at the talent show. Everyone loved his performance, and he won the first prize! His teachers and friends were proud of him. Even so, Ken told Brian that he was not funny, and that he would never be successful. Brian didn't understand why Ken said so, but he realized that it had nothing to do with him. He confidently continued to work towards his goal.As the years went on, Brian met more people like Ken. “You'll do a terrible job,” they said to him. Luckily, most people encouraged him and some helped him to become even funnier. He got a lot of opportunities to perform in movies. He was even invited to appear on television. His fans thanked him because his comedies made them feel good when they were unhappy.Now Brian is a big comedy star! He is doing what he loves best. He never feels stressed like those unkind people, and he laughs all day long!( )1. What did Brian love best when he was a student?A. Going to school.B. Helping classmates.C. Watching comedies.D. Meeting new friends.( )2. Brian decided to prepare for the show because ________.A. his friends liked his jokesB. he was invited by a TV stationC. he wasn't busy acting in moviesD. Ken was expecting his performance( )3. After winning the first prize, Brian ________.A. began to understand KenB. became a teacher of actingC. encouraged others to join himD. continued to work towards his goal( )4. Brian's fans thanked him because his comedies brought them ________.A. successB. happinessC. luckD. pridePassage 4(2018东营)We have heard about people who have special memories. Recently there has been a report about a woman from Australia who can remember almost every detail(细节) of all the events in her daily life.Rebecca Sharrock, 25, is one of just 80 people worldwide who have been indentified(确定) as having Highly Superior Autobiographical Memory (HSAM,超级自传体记忆症). It means she can remember every small event—which most people would forget within(在……以内) days—as if it had happened just minutes ago.“I remember my mum putting me in the driver's seat of a car and taking a picture of me when I was 12 days old,”she said. “That's my earliest memory. I remember every day since then. I can't tell all the dates exactly because I was too young to understand calendars, but I remember what I did that very day, what the weather was like and so on.”Rebecca can also reexperience taste. If she's eating something that she doesn't like, she thinks about Black Forest cake, her favorite food, and the memory willbe so strong that she can nearly “taste” it.However, sometimes her memories prove(证明) to be painful. Because they're not just events that she remembers. “When I relive(再体验) memories, the feelings return, too,” Rebecca said.“For example, I remember falling over when I was three at my grandparents' house and hurting my left knee. Talking about it now, I feel painful in my left knee.”“At night, I have to sleep with the radio/recorder and a soft light on,”she added. “If it's too dark or quiet, my mind would be filled with all these memories and I can't sleep.”( )1. Which is NOT TRUE about Rebecca?A. She has special memories.B. She is from Australia.C. She is 25 years old.D. She can remember every detail of all the events.( )2. What happened to Rebecca on the day when she was 3 years old?A. She was identified as having HSAM.B. Her mother put her in a car and took a picture of her.C. She started to understand calendars.D. She hurt her left knee at her grandparents'.( )3. Whenever she is reliving her memories, ________.A. she is happyB. she experiences the feelings againC. she feels pain in her kneesD. she can taste her favorite food( )4. What is the result of having HSAM?A. She can remember every event in her daily life.B. She can reexperience taste.C. She can relive feelings.D. All the above.( )5. From the passage, we can infer(推断)that________.A. HSAM can do her good, but it also brings her painB. she feels painful if she recalls her experiencesC. she can fall asleep while she is reexperiencing memoriesD. HSAM can greatly improve her living conditionsPassage 5(2018江西)Carlton Joseph is a fashion designer(服装设计师), but not just any fashion designer. He appears on television, he writes books, and he owns his own fashion house.Born in 1980, Carlton started designing clothes when he was eleven. His fatherowned a clothes store, and Carlton used to work there at the weekend. Then he did a design course at college.When he was 21, someone suggested doing a TV program. He made his first show “Ca rlton's Clothes” in 2004, and he wrote his first book in the same year. Since then he has written four more. Carlton got married to TV producer Susan Mills in 2005.Three months ago, Carlton started his new company. He called it “Design: Carlton”.At work Carlton always wears black trousers and a black coat, but at home, or when he goes out, he wears clothes with bright colors(red, blue and yellow). He is especially crazy about new glasses, he buys a new pair every few weeks. “I like to look different every day,” he says.Carlton started wearing glasses when he was twelve. He dyed(给……染色) his hair red when he was 18. It is still red, and this year, for the first time, he has grown a beard. “My wife likes it,_that's why” is his explanation. But his beard is black!( )1. How old was Carlton when he wrote his first book?A. 11.B. 21.C. 24.D. 25.( )2. What does the underlined word “it” refer to?A. Carlton's hair.B. Carlton's beard.C. Carlton's coat.D. Carlton's company.( )3. What is the main idea of Paragraph 5?A. Carlton likes to look different.B. Carlton is a hardworking person.C. Carlton is crazy about new glasses.D. Carlton loves wearing colorful clothes.( )4. Which of the following is true according to the passage?A. Carlton is just a common fashion designer.B. Carlton started his new fashion company in 2005.C. Carlton made his first show after he got married to Susan.D. Carlton got some design experience before going to college.Passage 6(2018无锡)This year the US will honour(纪念) one of the country's most famous writers—Mark Twain(18351910). Most readers know that his real name was Samuel Longhorne Clemens, but how many know where the pen name “Mark Twain” came from?The answer shows Clemens' colourful early life before he became a writer. “Mark Twain” was the cry shouted on a ship when the ship entered a part of a river that was two fathoms(6 feet)deep. “Twain” is an oldfashioned way of saying “two”. Twain trained as a ship pilot on the Mississippi river for two years, a time that he wrote about in the humorous Life on the Mississippi(1883).The famous river would become an important theme in many of his works—who could forget the journey of Huck and Jim along it in his most famous book, The Adventures of Huckleberry Finn(1884)?With little education, he had to teach himself how to write stories. Whenever possible, he would go to public libraries. There he spent much time reading andthinking, which greatly helped him with his writing.On the other hand, his life experiences gave him wonderful material to write about and attract readers. Twain wrote in a style that has been called “local colour” because it shows great knowledge of local people and their customs.This gift is very clear in the two books for which Twain is still celebrated today:The Adventures of Tom Sawyer(1876) and its followup The Adventures of Huckleberry Finn, which many people call “The Great American Novel”.The most amazing invention in the book is the voice of Huck himself. Huck did not enjoy schooling. It shows in the way he uses language, in a spoken style. Only a master like Twain could copy the way a young southern boy talked so well.( )1. What does the underlined word “gift” mean in the passage?A. Twain's talent for selfteaching.B. Twain's “local colour” writing style.C. Twain's good sense of humour.D. Twain's experiences as a ship pilot.( )2. According to the passage, what is the best part of The Adventures of Huckleberry Finn?A. The deep social meaning.B. The exciting life experiences.C. The special way that Huck talks.D. The nice view of the Mississippi.( )3. Which is the most suitable place in the passage for the sentence, “Twain did not come from the writer's background you might expect.”?A. At the beginning of Paragraph 2.B. At the beginning of Paragraph 3.C. At the beginning of Paragraph 4.D. At the beginning of Paragraph 5.( )4. What is the passage mainly about?A. Mark Twain's career as a great writer.B. Mark Twain's interest in describing local life.C. Mark Twain's achievements in American literature field.D. Mark Twain's life experiences which influenced his writing.Passage 7(2018南京)Rachel Carson(19071964) was a pioneer of the world's environmental movement through her writing about the protection of the natural world. Her 1962 book Silent Spring made her well known by many people. It describes the harmful changes in the environment of using toxic(有害的) chemicals on farmland.Carson's career started as a biologist in the US Bureau of Fisheries. ln 1951 she published her first book, The Sea Around Us, which became a bestseller. It made her rich enough to leave her job and devote her life to writing. She was a giftedwriter. Her next two books were also about the oceans and both topped the book sales lists.Carson's book Silent Spring completely changed the way America thought about nature. It painted a bleak(荒凉的) future for the whole natural world. It led to a nationwide ban(禁止) on the use of a deadly chemical called DDT, and other toxic pesticides(农药) that farmers used for their crops. Many people say the book led to the creation of America's Environmental Protection Agency.Since her death, Carson's name has continued to be connected with protecting the environment. There is now a yearly Rachel Carson Book Prize. Norway awards the Rachel Carson Prize to women who have made great contributions to the field of environmental protection. In 1980, 16 years after her death, she was awarded the Presidential Medal of Freedom, the highest civilian honour in America.( )1. What happened to Rachel Carson in 1962?A. She started to write books.B. She gave up working as a biologist.C. Her book The Sea Around Us sold well.D. Her book Silent Spring made her famous.( )2. What most probably made Rachel Carson leave her job?A. She got an award.B. She published Silent Spring.C. The Sea Around Us brought her enough money.D. The US government took notice of her researches.( )3. Why is the book Silent Spring important to America's environmental protection?A. It describes a silent spring.B. It topped the book sales lists.C. It changed how America thought about nature.D. It includes all Carson's research achievements.( )4. What does the underlined word “It” in Paragraph 3 mean?A. The book Silent Spring.B. The way America thought.C. The US Bureau of Fisheries.D. America's Environmental Protection Agency.( )5. Why was Rachel Carson awarded the Presidential Medal of Freedom?A. She published the book Silent Spring.B. She did a lot of researches for the US Bureau of Fisheries.C. She donated much money to the Rachel Carson Book Prize.D. She made great contributions to the environmental protection.题型三阅读理解专项训练一人物故事Passage 1【主旨大意】本文是一篇记叙文。
2018年陕西省中考数学试卷(有答案和解释)
2018年陕西省中考数学试卷
一、选择题(本大题共10小题,每小题3分,共30分)
1.计算 =()
A. B. C. D.0
【答案】C.
【解析】
试题分析原式= ﹣1= ,故选C.
考点有理数的混合运算.
2.如图所示的几何体是由一个长方体和一个圆柱体组成的,则它的主视图是()
A. B. C. D.
【答案】B.
【解析】
试题分析从正面看下边是一个较大的矩形,上便是一个角的矩形,故选B.
考点简单组合体的三视图.
3.若一个正比例函数的图象经过A(3,﹣6),B(m,﹣4)两点,则m的值为()
A.2 B.8 C.﹣2 D.﹣8
【答案】A.
【解析】
考点一次函数图象上点的坐标特征.
4.如图,直线a∥b,Rt△ABC的直角顶点B落在直线a上,若∠1=25°,则∠2的大小为()
A.55° B.75° C.65° D.85°
【答案】C.
【解析】。
中考真题(2018)第一节:阅读理解(共20小题,每小题2分,满分40分)阅读下面短文,从每题所给的四个选项(A、B、C和D)中,选出最佳选项,并在答题卡上将该项涂黑。
AThere were two fishermen named Tom and Jack.They were close pals.One day they went out to catch fish together and have a fish meal in the field.They sat at a distance and started hunting for fish.Tom got a big and beautiful fish in a few minutes.He was so happy and placed the fish in the ice box.He decided to cook the fish in the noon.He spent some more time and caught a few more fish.He decided to make a grand meal with the fish.Also,he froze a few fish to take them back home.After an hour or so,Tom went to Jack to see if he needed any help.Jack said no.In a few minutes,Jack caught a large fish.However,he put it back into the lake.Tom was surprised at his act,but he remained silent.Jack caught more big fish,and put them all back into the lake.Very frustrated,Tom angrily asked him,“Are you mad?Why do you put your fish back into the water?They are beautiful and big!”Jack replied,“I know they are big,but I don’t have the big pan(锅)to cook the big fish!So I’m looking for a smaller fish that fits my cooking pan!God is troubling me today.”…21.What did Tom and Jack go out for?A.To catch fish.B.To have a joy ride.C.To eat out together.D.To feed the fish in the lake.22.Why did Tom put his fish in an ice box?A.To keep it alive.B.To keep it fresh for his meal.C.To keep it from going away.D.To keep it away from his friend.23.What did Tom want to do when he went to his friend?A.To give him some fish.B.To offer some help.C.To ask him to cook his fish.D.To take some of Jack’s fish for himself.24.Why was Tom angry with his friend?A.He couldn’t understand his act.B.He was fond of eating big fish.C.He thought it was unfair for small fish.D.He didn’t catch any big fish himself.25.What would be Tom’s advice for his friend at the end of the story?A.Ask God to send him only small fish.B.Take a bigger pan with him next time.C.Change his fishing pole to catch small fish.D.Cut the big fish into small pieces to fit his pan.BYou could be a Teacher!Great chances for you to find out more withour3-day Teaching Taster Course!●Find out what it’s really like to be a teacher in a primary or secondary school and spend one day in school;●Learn about the different roads to teaching—full time,part time,including how you can earn while you train;●Find out about the job, e.g.teacher’s pay and the conditions of the work;●Our courses are funded(资助)by Teachers Training Agency and so only cost you£20.Our next courses are being held:Lincoln(Lincolnshire)25to27June2018Scunthorpe(Nth Lincolnshire)16to18September2018Stamford(Lincolnshire)3to5December2018Beverley(East Yorkshire)21to23January2019Boston(Lincolnshire)11to13February2019Interested?For an application form(申请表)and full details,Tel:01476512780Email:enquiries@26.Where is this ad.from?A.Australia.A.C.Canada..27.You might be interested in this ad.if you________.A.are already a teacherB.want to be a teacher in the futureC.want to work for the Teachers Training AgencyD.are looking for a good school for your children28.What can you get out of this course?A.What it takes to be a good teacher.B.A place to teach in a local school.C.A quick taste of what teaching is about.D.A chance to visit different parts of the country.29.How many courses are on the way if you miss this one?A.7.B.6.C.5.D.4.30.Which of the following is true according to the ad.?A.The course lasts continuously for five months.B.£20each cannot cover the cost of the course.C.The course is not open to people from other countries.D.You have to go to Emdirect in person if you want to have a try.COn September13th,I woke up in the best mood.It was a late start,so I got to sleep in.Not only did I get my full eight hours of sleep,but an additional two more hours as well.I got ready, danced in my room to my favorite music while I picked out my clothes,made my lunch,and was on my way to school.I arrived at9:50a.m.Little did I know,in the next20minutes,my life would change forever.As I got out of my classroom,there he was,holding the gun.Although everything happened so fast,in a matter of about4minutes,I remember it clearly.I remember every face I saw,and I remember every sound I heard.I remember the fear and the panic of the unknown.And lastly,I remember running.Running for my life.I ran down the stairs,out of the school’s front doors,and down the street to the primary school.I remember looking down at my feet.As I looked down I thought to myself,“How am I running so fast?”I finally made it to a safe classroom,and20other students and I settled in for lockdown.We stayed close to one another and cried.It felt as though the tears going down our faces would never stop.We passed our phones around to text our loved ones that we were safe and that there was a school shooter,shots were fired,and4students were injured thus far.The lockdown lasted about30minutes,even though it felt like forever.Our headmaster made his way to our room and explained that the shooter had been caught and we were all going to make our way to the football field.31.How did the writer feel before going to school?A.Relaxed.B.Worried.C.Scared.D.Puzzled.32.What does the phrase“sleep in”probably mean in Paragraph1?A.sleep in bedB.sleep with clothes onC.sleep with face coveredD.sleep longer than usual33.What did the students do when the shooting began?A.Calling the police for help.B.Running away in all directions.C.Fighting back against the shooter.D.Texting their beloved ones about it.34.Where did the writer find safety in the shooting?A.On a football field.B.In a neighboring school.C.In a classroom of her school.D.Back at her own home.35.What can we tell from the story?A.The headmaster didn’t care about his students.B.There was more than one shooter in the killing.C.Not all the21students took phones with them.D.The shooter killed himself in the end.DChinese buyers used to prize foreign brands,thinking that products made by American or European companies are of higher quality(质量)than Chinese ones.Increasingly,that’s no longer the case.Chinese people born before1985generally think that foreign brands are better than Chinese ones,billionaire William Li told Business Insider during a recent interview on CCTV9.But for those who were born after1985,it is a different picture.“When I first went to the United Kingdom in1997,I thought that the difference between China and Europe was quite big,”Li said.“But for those born in the1990s,when they visit Europe or the US,they do not think there is a big difference.”The change in thinking among Chinese buyers is showing up in many markets in China where western companies used to control.A study by Credit Suisse published in March found that young Chinese buyers are increasingly showing a“home brand bias.”More than90%of young Chinese buyers would prefer to buy home appliance brands, according to the study.Meanwhile,home companies producing food,drinks,or personal care products increased their share of the market by3.3%over the last ten years to nearly70%.“Chinese buyers,especially the younger ones,don’t just believe that foreign brands are better.Right now,Chinese buyers think China is good and‘Made in China’is not bad at all,”Charlie Chen,head of China buyer research at Credit Suisse,told South China Morning Post in March.The Chinese smartphone market is controlled by home companies Huawei,Oppo,Vivo,and Xiaomi.Apple is the only foreign brand in the top five,but it has lost large ground to the home brands in recent years.Its market share is believed to be down to37%from a2015high of54%.36.What is this passage mainly about?A.The quality of“Made in China”.B.The change in Chinese buyers’thinking.C.Chinese products in the eye of foreigners.D.Difference between older and younger Chinese buyers.37.Which of the following is true according to the text?A.More and more foreigners go to buy Chinese products.B.Foreign products are more expensive than Chinese ones.C.More and more Chinese buyers prefer Chinese products.D.Older Chinese people don’t like foreign products any more.38.Which fact best explains“home brand bias”?A.Apple had a market share of54%in2015.B.More than90%of young Chinese buyers prefer home brands.C.Chinese people born before1985think that foreign brands are better.D.William Li found a big difference between China and Europe in1997.39.Who did most of the research for this report?A.Credit Suisse.TV9.C.South China Morning Post.D.Business Insider.40.What’s the best title for this passage?A.Chinese products get more popular at homeB.Young Chinese are crazy for foreign brandsC.“Made in China”is welcomed all over the worldD.Apple has Lost large ground to Huawei in China第二节:完形填空(共15小题,每小题2分,满分30分)阅读下面短文,从短文后各题所给的四个选项(A,B,C和D)中,选出可以填入空白处的最佳选项,并在答题卡上将该项涂黑。
阅读理解(一)APeople in Los Angeles are known for their love of cars. The city is very large, and its public transportation is slow. So people drive everywhere. But now, a group of bicyclists are trying to get people out of their cars and on bikes.Devon Fitzgerald say s he has to be careful when he rides his bike in the streets. ―A lot of people are in a rush, and it's very difficult to keep careful, for they would rather care for their speed than your safety.‖ Although riding a bike to work can be dangerous, he prefers it to a car. ―It's much simpler than driving a car. For example, I don't have to worry about parking.‖Roger Rosas drives to work. "You always have to make sure you look to the other side because someone would rush across by bike. Or you can easily get into an accident. "To make bicycling safer, some people who live and work near each other are riding to work together, which they call a "bike train". Nona Varnado helped create the group L. A. Bike Trains. "You're in a big group. If you're afraid of riding alone, you can now ride with experienced riders. " Nona said that people would feel safer by riding together in a group.1. People in Los Angeles are known for their love of_________.A. carsB. busesC. subwaysD. bicycles2. Devon Fitzgerald finds it _________ to ride his bike in the streets.A. safeB. dangerousC. boringD. exciting3. Devon Fitzgerald likes riding a bike better because__________.A. it's much cheaperB. it is full of funC. it's safer everywhereD. it's much easier4. From the passage we know that_________.A. riding in a ―bike train‖ can help people feel saferB. Devon Fitzgerald helped to create L. A. Bike TrainsC. Roger Rosas prefers riding a bike to driving a carD. people can easily get into an accident when riding togetherBI still remembered my first day of second grade. I was led to a room. No teacher yet. Girls talking. Boys trying to kill each other.I took some paper and a pencil, picked a desk, and went to work. Minutes later, a girl came over and sat on top of my desk.―What're you doing?‖ she said.―Writing to 100,‖ I replied.―Is that you can do?‖―No,‖ I said.Then I rose from my seat to get my pencil sharpener. I had no idea that when I stood, the desk would fall over and hurt her leg.Her name was Jane. From that day on--she was my best friend. Wherever we went--to school or church or basketball games, Jane saved me a seat or I saved one for her.Many years later, after college, I moved to California and married. Jane stayed in our hometown to be a social worker. We were friends for more than 50 years. After her death seven years ago, I still think of her often, especially at the start of the school year.TV ads try to tell us what children need for school—new shoes, clothes, backpacks. But really, children's needs are simple. Besides the basics—to be fed, cared for, and loved—they need the gift of friendship.For years, I feared how people saw me. But one day, I finally understood. I didn't need to be smart or pretty or popular. I just needed to be kind.My grandson Henry recently finished his preschool and received a prize for ―Friendship‖. Even an Olympic medal wouldn't make me prouder! I think children need to know that they are loved. They need to know that they have all they need and the best way to win friends is to be one.5. When she came into the classroom, the writer ________.A. went to talk with Jane quicklyB. helped Jane write the numbers to 100C. worked quietly at her desk aloneD. was afraid that others would fight with her6. From the passage we know that__________.A. the writer's leg was hurt on the first day of schoolB. the two girls were close friends until Jane diedC. Jane often helped the writer to do some social workD. the two girls stayed in the same city after college7. Henry received a prize for "Friendship" probably because _________.A. he was kind to othersB. he was smart at his schoolworkC. he was loved by his grandmaD. he joined in the Olympics8.The best title of this article would be__________.A. My Best Friend JaneB. How to Choose FriendsC. My First Day at SchoolD. Friendship ValuesCThe winter of 1948 was very difficult for our family of eight living in Knoxvile, Tennessee. Unfortunately, Dad became ill and soon was out of a job. I was only 8 years old and my younger brother, Buddy was 7. After school we went to pick coal(煤) that fell from the coal train along the railroad near our home. When the train slowed down, we ran alongside it. After the train passed, we picked up the fallen coal.One day, the train stopped for a short time unusually. My brother and I were digging around in the snow when the train's fireman came to the window and shouted to us, ―Why are you boys digging in the snow? Are you looking for gold?‖ he laughed.―No, sir,‖ I replied, ―We are finding coal.‖―Why doesn't your daddy buy coal? It's really dangerous here.‖―Our daddy is very sick and we have no money to buy food and coal,‖ I answered.The fire man turned and went inside. After a moment, he shouted again. ―Hey! Bring that coal bucket(桶子) here. I got something for you.‖ Then the fireman filled our bucket with clean coal. We were happy with his gift, and we knew we could go home early that day.He smiled the kindest and warmest smile I had ever seen. ―You two boys come here the day after tomorrow and I'll throw off some coal.‖Two days later, Buddy and I stood by the railroads as the train slowed down. The fireman waved to us, then disappeared. Suddenly, some coal and a piece of red cloth came out. In the red cloth were two pieces of bubble gum(泡泡糖) and a new one-dollar bill.All that winter, three days a week, we received a bucket of coal, a gift and, sometimes, money.I never knew the person's full name, but to our family, he was a guardian angel.9. The winter was very difficult for the family because____________.A. the weather was colder than everB. they couldn't afford food or coalC. the writer's father was paid a littleD. they couldn't get help from the government10. We can learn from the passage that___________.A. in order to help his family the writer didn't go to schoolB. the fireman thought the boys were very brave to go near the trainC. the train would stop for a while every time near their homeD. the writer and his brother collected fallen coal to help their family11. The underlined sentence ―he was a guardian angel‖ in the last paragraph means ―___________‖A. the fireman was a close friend of the familyB. the fireman often gave them good foodC. the fireman protected the two boys from dangerD. the fireman had pity on the family and offered them help12. The writer wrote the story mainly to____________.A. tell us to be hopeful in times of difficulty, no matter how bad it isB. remember a difficult time during his childhoodC. show a little kindness can make a great difference to people in needD. show how he and his brother helped his family out(二)Dear Sir or Madam.One of the teachers at my school in New York tells me that your school has summer course. I am planning to go to Beijing next summer and would like to take a short one-month course.I am 18 years old and have been studying Chinese for six years. I was born in the USA and have never been to China before. I am going to study Chinese at the university. I think the course will help me improve my Chinese.Could you send me a catalogue(目录) and application form (申请表)? I would also like information about Beijing and other places nearby. I hope to do some travelling when the course is over.Thank you! I am looking forward to your replyVery truly yours,Jim Green1. Jim Green is a student from_______. .A. AmericaB. ChinaC. CanadaD. Australia2. He was twelve yearsold when he started to_______.A. go to schoolB. learn ChineseC. study in ChinaD. travel in Beijing3. How many times has he been to China before?A. Once.B. Twice.C. Many times.D. Never.4. He will come to China next summer to_______.A. improve his ChineseB. visit friendsC. look for jobsD. teach summer course5. He will probably____ after the summer course.A. graduate from universityB. work in this schoolC. take a trip in BeijingD. post his application formMany kids do housework such as doing the dishes, making the bed, and folding the clothes.In exchange, they get some money or other computer time.Paying kids for housework is one of the most popular topics, especially at a time when everyone is more careful about money. Some parents think since adults are paid to do their jobs, we should pay kids for everyday housework.But some people don't think kids should get rewards(报酬) for doing housework. Susie Walton, an expert, believe that by rewarding kids, parents are sending a message that work isn't worth doing unless you get something in return. ―Running any kind of housework is a team effort,‖ Walton said. ―A home is a living space for everyone in the family. It's important for kids to see that we all have responsibilities in the house, and families decide how they want their home to look, and how they are going to keep it looking like what they want.‖Other people believe that getting a reward encourages kids to do housework, and it also teaches them real world lessons about how we need to work to get money. There are also apps(程序) that gives kids points and digital gifts that can be redeemed(兑现) either online or in the real world. ―Our goal is to give kids lawful power so they can get rewards,‖ says Chris Bergman. ―And kids need rewards to help encourage them. ‖6. Which of the following housework is NOT mentioned in Paragraph 1?A. Washing the dishes.B. Cooking meals.C. Folding the clothes.D. Making the bed.7. The underlined phrase ―in return‖ in Paragraph 3 has the same meaning as ―_____‖.A. as a rewardB. for punishmentC. on saleD. under control8. What's Walton's idea in the passage?A. Running exercise is a kind of team work.B. People work to get some rewards.C. Kids have responsibilities in the house.D. Doing the housework in only the parents' job.9. According to Chris Bergman, kids should be encouraged to ______.A. do housework without rewardsB. do more houseworkC. stay away from houseworkD. do housework by getting rewards10. Which is the best title for the passage?A. Kids Should Study as Well as Doing HouseworkB. Let Children Do Some HouseworkC. Should Kids Be Rewarded for Doing HouseworkD. Doing Housework Is Good for Children's StudyCLast summer I went to one of the world's most famous historical places, the Forbidden City in Beijng, China. It was the home of the emperors of the last two dynasties (朝代) in China, the Ming and Qing Dynasties.The Forbidden City was built in 1420. The palace has over 10,000 rooms. It was where the emperors dealt with the official business with their ministers.In Mandarin, The Forbidden City is called the Purple Forbidden City. However, the color of the palace itself is not purple. The color purple stands for power of the great emperors of China. It was so sacred(神圣的) that the commoners could not even dream of ever going in.The emperors also had some of the largest festival celebrations at the Forbidden City. During Chinese New Year, the emperor would invite all the members of his family and his officials to a banquet. The banquet had a hundred and eight Chinese dishes. It was such an expensive banquet that it could feed a commoner's family for three generations(代).Right now The Forbidden City is known as a historical site for tourists from all over the world. Everyone can go in there. It is a museum with priceless Chinese antiques (古董) and treasures in it.I really learned a lot about the Chinese culture and its history from this trip to The Forbidden City. It was like a dream come true to go on the trip and see the things that I have always wanted to see.11. How long is the history of the Forbidden City?A. About 600 years.B. More than 600 years.C. 1,420 years.D. Over 10,000 years.12. We call the palace the Purple Forbidden City because the color purple is the symbol for ____ of the emperor.A. powerB. fameC. wealthD.health13. What's the Chinese meaning of the underlined word ―banquet‖ in Paragraph 4?A. 表演B. 比赛C. 展览D. 宴会14. Which of the following is NOT true about the Forbidden City in the passage?A. The Emperor lived there.B. The wall of the City.C. It is a historical place for visiting.D. The emperor had festival celebrations there.15. In the passage the writer wants to show us _____of the Forbidden City by comparing its past with present.A. the beautyB. the treasuresC. the changes in useD. the building process(三)ALearn English in New ZealandLearn English in New Zealand at Language Schools New Zealand (LSNZ). Our Christchurch and Queenstown schools in the South Island of NZ are the perfect places to learn English.What is your dream?Do you dream of speaking English very well?Do you dream of travel, making friends, a lifestyle using English?LSNZ will help you to achieve your dream.Language Schools New Zealand Christchurch and Queenstown are in the fascinating South Island of New Zealand. Both English schools are fully recognised(认证)by NZQA and are in beautiful NZ places. LSNZ offers many kinds of English courses including General English, Exam Preparation, Study & Ski and more. Our friendly hard-working staff have helped many students from all over the world achieve their dream of using English in their lives. We invite you too to become a member of the LSNZ family.LSNZ English Courses.Enroll(注册)now for a LSNZ English course –we promise your English will improve and offer 2 NZ schools with excellent teachers and small class sizes.General English●IELTS●Study & Ski●Combo CourseCambridge, Toeic & Pitmans Exam preparation courses are also offered at both schools.1. According to the text, Christchurch and Queenstown school .A. lie in the North IslandB. are members of LSNZC. own the perfect places to visitD. teach only local students2. The text tells us that LSNZ .A. provides over four coursesB. practices large-class teachingC. designs lots of examsD. has many teachers from abroad3. Those who want to will most probably be interested in this text.A. look for jobs at LSNZB. build language schoolsC. improve their EnglishD. learn about New ZealandBSydney Fredette has a lot of things to deal with. Not only is she a high school student, but she has also set up her own organization, Beary Merry Christmas. She volunteers(自愿)to serve poor kids and families in Orange Country in California, US.To remember her best friend who died of cancer nearly 10 years ago, Fredette decided to serve those in Orange Country who are less lucky than she is.She began with the simple idea of collecting donated(捐赠的)Build-A-Bears,the popular toy animal that is made by children themselves in the stores' workshops. Fredette then gave them as gifts to the homeless children in California during the holiday season.With donations at more than 100 bears a year, Fredette and volunteers host activities every year, where volunteers not only give out the bears, but also clothing, meals, and other things.Not wanting to limit(限制)the giving to just the holiday months, Fredette now hosts other activities for Valentine's Day, Mother's Day and Halloween, providing the chance for her volunteerteam to make a difference through the year.―I love making relationships with the people I serve,‖ Fredette said. ―The thanks they have, hearing their stories and seeing how happy they are, it's so cool.‖Future plans for Fredette include building a public food bank and providing aself-development class for students in her school who will soon attend college.Heading to college herself in the fall, Fredette is looking to stay local and continue to help out i n her hometown. In fact, she was regarded as a ―Dreamer & Doer‖ not long ago for her work in improving her community, along with 32 other high school students.4. Fredette started her own organization to .A. keep her life busyB. help poor peopleC. look after the sickD. thank her best friend5. What can we learn about Beary Merry Christmas?A. It holds one activity a year.B. It offers service around America.C. It buys bears from the stores.D. It gives out other things besides bears.6. It can be inferred(推断)that Fredette .A. likes telling people storiesB. dreams of being a teacherC. is pleased with what she doesD. plans to leave California for college7. What can be the best title for the passage?A. Giving back to societyB. Getting on well with othersC. Providing a food bankD. Improving community collegesCMore Chinese universities are opening their libraries to the public, allowing people to enjoy reading during normal time and the vacations.But for some students, including Wang Ling, 21, in Sun Yat-sen University, this practice has caused headaches. ―Members of the public come to our libraries more for sightseeing than reading,‖ said Wang.―They sometimes even b ring their kids along, and take photos as if it were a place of interest.‖Wang has found it hard to get a seat during busy times. Being short of space is a common problem for university libraries in China.However, this is not the only reason why students dislike their libraries being open to members of the public. They fear that the quietness of the libraries will be influenced because of visitors' rude behavior.Chen Jie, 18, a student in Tongji University, is one who would be against opening to the publ ic. ―I have been to a public library before. People were chatting loudly or speaking on cell phone so you can hardly read,‖ Chen said. She notices teachers doing serious reading and feels their concentration(专注)has influenced her. ―If too many strangers st ay here, the whole library will be a noisy place and it's difficult for us to study quietly,‖ she said.Will there be alternative(可替代的)ways to share those libraries? Some experts consider that university libraries can prevent the public from entering certa in areas. ―We might keep magazines for academic research only for teachers and students,‖ said Zhu Lina, library director in Jinan University.Working together with the community library is another solution. ―It's possible that a member of the public can order a book in our library over the Internet,‖ Ge Jianxiong, the library director in Fudan University said. ―We'll send it to a public libraries close to their home.‖8. We can see from the passage that Wang Ling .A. hates to study in the libraryB. prefers sightseeing to readingC. feels good to play with kidsD. is a university student aged 219. In Chen Jie's opinion, visitors to university libraries may .A. take up too much spaceB. break the peace thereC. make teachers relaxedD. get students to read more10. The writer mentions two libraries directors' words to help explain how to .A. manage libraries onlineB. keep the public politeC. share university librariesD. do scientific research11. Where is the passage most probably taken from?A. A newspaper.B. A library guide.C. A story book.D. A notice board.DHave you ever seen a car without a driver? It sounds crazy, but these computer-driven driverless cars will soon be filling roads near you. Companies like Google and Tesla have been designing and testing these cars, and the technology is there.So how? The cars have sensors(感应器)all around which can find other cars and objects in the road. Road signs are read by cameras, and satellite navigation systems(卫星导航系统)are used so the car knows how to get where you want to go. All you have to do is type in the address! Finally, a central computer system takes in all the information that it receives from the sensors and cameras and works out when to speed up, stop and turn.Sound like your idea of heaven(天堂)? Sitting back, looking out of the windows and even watching a film or reading a book while ‗driving' would be possible with this new technology. You wouldn't have to worry about remembering directions to where you're going. In addition, computers would also drive more safely than people — they would obey the rules and have quicker action times when in dangerous situations.However, there are many drawbacks of driverless cars. Computers would have difficulties making ethical(道德的)decisions: if a child ran into the road, would the computer choose to hit the child or turn suddenly and potentially kill the car's passengers? Moreover, I personally find driving fun –I'd miss never driving a car myself. There would also be many other decisions to be made –should children, or drunk people, be allowed in a driverless car by themselves? Or would there need to be a person with a driving license in the car at all times?I'm not certain I'd want a driverless car – but it's only a matter of time before they'll become more affordable and popular on our roads.12. When using a driverless car, you need only .A. read the road signs carefullyB. check the camerasC. put the address into the computerD. remember the directions13. The third paragraph mainly tells us about the of driverless cars.A. instructionsB. standardsC. advantagesD. tests14. The underlined word ―potentially‖ in Paragraph 4 means ――.A. possiblyB. successfullyC. especiallyD. naturally15. What's the writer's opinion about future driverless cars?A. They'll cause more accidents.B. They'll be less expensive.C. They'll use less energy.D. They'll run much faster.(四)ALast year, I went to Beijing Qizhi Special Education School for community service(社区服务).Before we took the bus, my friend asked me a question, ―Why are you here?‖ I did not know how to answer the question.The school was not far from my school, but it looked like it was in a different world. A group of children were waiting for us. A boy walked toward me. He held my hands and pulled me to the ground. I kissed the earth and tasted nature.I could not understand what he was doing at first, then I was very angry. Though I was very angry, I controlled my anger.A teacher stopped this awkward(尴尬的)silence when she shouted at the boy. ―What are you doing right here, right now?‖ she said. ―You w ill never see your mom again if you keep doing this. Now, say sorry!‖ ―Sorry,‖ he cried fearfully and nervously. I said nothing, but I realized something about t his child. After lunch I asked the teacher for information about the child's parents.She said that the child was very different from other students because of an illness. His family could not afford to treat him. He needed the kindness of his family, but they had abandoned him. So he depended on the supportfrom the teachers and community service workers like us.I suddenly realized I could answer the question my friend asked me at the beginning of the day.Community service workers help others and make everyone feel better. There are so many people in the world that need help. Playing with lonely children may not make a big difference. But it can light a corner in the children's hearts, making them know they are loved by people.1. How did the writer reach Beijing Qizhi Special Education School?A. By train.B. By car.C. By bus. C. By taxi.2. Why did the writer get angry?A. Because a boy held the writer's hands.B. Because the writer did not like to taste nature.C. Because a boy pushed the writer to the ground.D. Because a boy was impolite to the writer.3. The boy acted differently from others because _______.A. he was sickB. his parents didn't like himC. he was nervous and fearfulD. he always lived with teachers4. The underlined word ―abandoned‖ most probably means ―_______‖.A. hurtB. leftC. soldD. forgotten5. From the passage we can learn that the writer __________.A. helped so many people in the worldB. played with the lonely boy after lunchC. learned the meaning of community serviceD. wasn't good at answering the questions about community serviceBThe Silk Road is the name of different roads that long ago connected Europe, Africa and Asia. People reached these different places along these roads. Scientists believe people began to travel the Silk Road about 3,000 years ago. By the time the Chinese silk trade became important in the world, the Silk Road covered almost 6,500 kilometers. It spread from Rome to China, which is from the West to the Far East.Traders travelling along the Silk Road carried silk, of course. They also carried and traded spices(香料),cloth, valuable stones and gold.There is a famous old story along the old road. It is said that Roman soldiers(士兵)travelled through central Asia. They started to live somewhere near the ancient Chinese village of Liqian. Some of these Romans married local Chinese women and the story of blue-eyed villages of China was started.During its busiest period, the Silk Road allowed people from many different cultures andcountries to meet each other and mix. The Silk Road allowed the sharing of valuable goods and new ideas. These included people and trading goods from the Mediterranean, Persian, Magyar, Armenian, Bactrian, Indian and Chinese areas. All these peoples travelled the Silk Road, and they shared goods, stories, languages, and cultures.In modern times, the old Silk Road routes(路线)are still used, but now they are crossed by trains instead of camels and horses. There is even a Silk Route Museum in Jiuquan in China. It has over 35,000 objects from all along the Silk Road. In this way, China protects the history of many countries and peoples.6. How many kilometers did the Silk Road cover?A. About 3,000.B. Nearly 6,500.C. Almost 2,000.D. Over 35,000.7. Traders carried all kinds of goods along the Silk Road. Which of the following is not mentioned in the passage?A. Silk.B. Cloth.C. Gold.D. Tea.8. Who married ancient Chinese women in the story of blue-eyed villages of China?A. Asian soldiers.B. African soldiers.C. European soldiers.D. American soldiers.9. What can we infer(推断)from the passage?A. Valuable things could not be sold along the Silk Road.B. The Silk Road allowed people from different countries to mix.C. Ancient Chinese along the Silk Road may be able to speak different languages.D. The objects in the museum in Jiuquan in China are from all along the Silk Road.10. Which part of a magazine can this passage come from?A. History and Geography.B. Sports World.C. Man and Animals.D. Popular Science.CWe often face the following situations in our daily life:●The woman next door plays her piano after 12 o'clock at night.●The family across the street never cleans up their yard. The rubbish blows into youryard.●The man next door always parks his car in front of your drive.。
2018年中考数学填空题的解答策略复习题(人教版有答案)填空题的解答策略
张中元
中考填空题属客观性试题,一般题目短小精干、跨度大、容量大、覆盖面广,答案简短、明确、具体,不必填写解答过程,答卷方式简便,评分客观、正、准确但它有本身的特点,不像选择题有答案可供选择,这就避免了选择项所起的暗示或干扰作用,避免了考生有瞎猜的侥幸心理,从这个角度看,它能够比较真实地考查出学生的真实水平
中考填空题考查的内容多是“四基”方面的内容,一般是容易题或中档题,大多数是计算和概念判断性的试题,因此,同学们在做中考数学填空时,切忌“小题大做”,既要认真审题,看清楚题目中的条要求,又要快速地找到解决问题的方法下面摘取部分填空题,谈谈其解题策略,供同学们复习时参考
一、直接法
直接法是从题设条出发,利用定义、定理、性质、法则等知识,通过计算、分析、推理得到正确答案的解法,它是较普遍使用的常规方法
例1(9a的值为_________
2(1,-1),(1,-1),则顶点D的坐标为_________
3(55°=70°,故答案为70°
例4无论m为任何实数,二次函数y=x2+(2-m)x+m的图象都经过的点是________
分析由于m可以为任何实数,所以不妨设m=2,则y=x2+2,再设m=0,则y=x2+2x,然后解方程组求出的解即为图象所经过的点解∵m可以为任何实数,∴不妨设m=2,则y=x2+2,再设m=0,则y=x2+2x,解方程组得∴二次函数y=x2+(2-m)x+m的图象都经过的点是(1,3)
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C .底边上的高是 ⎛ 3⎫2 12- ⎪ = ,可知是顶角 120°,底角 30°的等腰三 (专题五阅读理解问题一、选择题1.(原创题)如果三角形满足一个角是另一个角的 3 倍,那么我们称这个三角形为“智慧三角形”.下列各组数据中,能作为一个智慧三角形三边长的一组是( )A .1,2,3C .1,1, 3B .1,1, 2D .1,2, 3解析 A .∵1+2=3,不能构成三角形,故选项错误;B .∵12+12=( 2)2,是等腰直角三角形,故选项错误;1 ⎝2 ⎭ 2角形,故选项错误;D .解直角三角形可知是三个角分别是 90°,60°,30°的直角三角形,其中 90°÷30°=3,符合“智慧三角形”的定义,故选项正确.答案 D2.改编题)若一个 n 位数中各数字的 n 次幂之和等于该数本身,这个数叫做“自恋数”.下面四个数中是“自恋数”的是 ( )A .66C .225B .153D .250解析 ∵62+62=36+36=72≠66,13+53+33=1+125+27=153,23+23+ 53=8+8+125=141≠225,23+53+03=8+125+0=133≠250,故 66,225, 250 都不是自恋数,153 是自恋数.故选 B.答案 B二、填空题3.(改编题)定义新运算:对任意实数 a ,b ,都有 a ⊗b =a 2-b 2,例如,3⊗2=32(-22=5,那么 2⊗1=________.解析 根据题意,得 2⊗1=22-12=4-1=3.答案 34. 改编题)若规定一种运算为:a ★b = 2(b -a ),如 3★5= 2(5-3)=2 2.则 2★ 3=________.解析答案2★ 3= 2( 3- 2)= 6-2.6-2三、解答题⎪a b ⎪ ⎪a b ⎪5.(改编题)阅读材料:对于任何实数,我们规定符号 ⎪ ⎪的意义是 ⎪ ⎪=⎪c d ⎪ ⎪c d ⎪⎪1 ad -bc .例如:⎪ ⎪3 2⎪ ⎪-2 4⎪⎪=1×4-2×3=-2,⎪ ⎪=(-2)×5-4×3=-22.4⎪ ⎪ 3 5⎪⎪5 (1)按照这个规定请你计算⎪⎪7 6⎪⎪的值; 8⎪⎪x +12x ⎪ (2)按照这个规定请你计算:当 x 2-4x +4=0 时,⎪ ⎪的值.⎪x -1 2x -3⎪⎪5 6⎪ 解(1)⎪ ⎪=5×8-6×7=-2.⎪7 8⎪(2)由 x 2-4x +4=0,得 x 1=x 2=2,⎪x +12x ⎪ ⎪3 ⎪ ⎪=⎪ ⎪x -1 2x -3⎪ ⎪1 4⎪ ⎪=3×1-4×1=-1. 1⎪6.(原创题△)若 ABC 所在的平面内的一条直线,其上任意一点与△ABC 构成的四边形(或三角形△)面积是 ABC 面积的 n 倍,则称这条直线为△ABC 的 n 倍线.如图 1,点 P 为直线 l 上任意一点,S 四边形 P ABC =3 △S ABC ,则称直线 l 为△ABC的三倍线.(1)在如图 2 的网格中画出△ABC 的一条 2 倍线;(2)在△ABC 所在的平面内,这样的 2 倍线有________条.解(1)如图所示:(2)在△ABC所在的平面内,这样的2倍线有3条.。
2018中考英语模拟题阅读理解12篇(人教版新目标带答案)阅读理解1Sports are important in English life The people of England are sports lovers Some of the world’s famous sports began here such as football and cricketFootball is a game played in winter and early morning Lots of people play football in parks or playgrounds just for fun With hundreds of year’s history, it is one of the most important sports in England The English love football very much and they turned most of their main players into famous persons David Beckham and Bobby Charlton became heroes for many child ren The most interesting part of the English football year is the FA(Football Association) Cup Final each May1 Sports are ________ in English lifeA impotantB not importantC unpopularD impossible2 Football is a fast game played _________A in winterB in early springC in summerD A and B3 A lot of people in England play football in _________A fieldsB school hallsC parks or playgroundsD Gyms4 David Beckham and Bobby Charlton became heroes for many _________A teachersB childrenC workersD farmers5 According to the passage, the FA(Football Association) Cup Final is in _______A each AprilB each JuneC each MayD each August1-5 ADCBC2。
2018年中考数学选择题的解答策略复习试题(人教版带答
案)
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选择题的解答策略
左丁政
中考数学的选择题为单项选择题,它属于客观性试题,概念性强,覆盖面广;选择题的解答情况,直接影响了考生的心里情绪和分数的高低,是数学得分的关键
解答中考数学选择题的基本思路是根据解题指令的要求,充分利用题目提供的信息,排除迷惑支的干扰,正确、合理、迅速地从选择支中选出正确的答案解答中考数学选择题的常用方法有以下几种
一、直接法
直接从题目的条出发,根据所学过的定义、定理、式、法则等准确地运算,严密地推理,得出正确的结果,然后与四个选项进行比较,作出判断
例1(MC=5-2=3故选C
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1(1=0配方后可变形为( )
A(x+4)2=17 B(x+4)2=15 C(x-4)2=17 D(x-4)2=15
2(1)=-15
D多项式t2-16+3t因式分解为(t+4)(t-4)+3t
分析利用排除法,根据矩形的性质,全等三角形的判定和分式方程的解法以及因式分解对各选项逐一分析判断即可得解
解矩形的对角线互相平分且相等,但不一定互相垂直,因此,A 是假命题;两边和一角对应相等的两个三角形不一定全等,因此,B 是假命题;C是真命题;多项式t2-16+3t因式分解为(t+4)(t-4)+3t 错误,是假命题故选C
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【真题】2018年青岛市中考数学试题(附答案Word版)东省青岛市2018年中考数学试题
第Ⅰ卷(共24分)
一、选择题本大题共8个小题,每小题3分,共24分在每小题给出的四个选项中,只有一项是符合题目要求的
1观察下列四个图形,中心对称图形是()
A. B. C. D.
2斑叶兰被列为国家二级保护植物,它的一粒种子重约00000005克将00000005用科学记数法表示为()
A. B. C. D.
3如图,点所表示的数的绝对值是()
A.3 B. C. D.
4计算的结果是()
A. B. C. D.
5如图,点在上,,点是的中点,则的度数是()
A. B. C. D.
6如图,三角形纸片,,点为中点沿过点的直线折叠,使点与点重合,折痕现交于点已知,则的长是()
A. B. C.3 D.
7如图,将线段绕点按顺时针方向旋转,得到线段,其中点的对应点分别是点,,则点的坐标是()
A. B. C. D.
8已知一次函数的图象如图,则二次函数在平面直角坐标系中的图象可能是()
A. B. C. D.
第Ⅱ卷(共96分)
二、填空题(每题3分,满分18分,将答案填在答题纸上)
9已知甲、乙两组数据的折线图如图,设甲、乙两组数据的方差分别为,。
专题复习(二)阅读理解题类型1 新定义、新概念类型类型2 学习应用型类型1 新定义、新概念类型(2018十堰)14。
对于实数a ,b ,定义运算“※”如下:2a b a ab =-※,例如,25355310=-⨯=※.若(1)(2)6x x +-=※,则x 的值为 .(2018湘西)(2018铜仁)(2018临沂)19。
任何一个无限循环小数都可以写成分数的形式,应该怎样写呢?我们以无限循环小数0.7,为例进行说明:设0.7x =.由0.7=0.7777..。
可知,107.7777x =。
...所以107x x -=方程。
得79x =,于是,得70.7=9。
将0.36写成分数的形式是______________. (2018吉林)(2018潍坊)10.在平面内由极点、极轴和极径组成的坐标系叫做极坐标系如图,在平面上取定一点O 称为极点;从点O 出发引一条射线Ox 称为极轴;线段OP 的长度称为极径点P 的极坐标就可以用线段OP的长度以及从Ox 转动到OP 的角度(规定逆时针方向转动角度为正)来确定,即(3,60)P 或(3,300)P -或(3,420)P 等,则点P 关于点O 成中心对称的点Q 的极坐标表示不正确的是(D )A .(3,240)QB .(3,120)Q -C .(3,600)QD .(3,500)Q -(2018巴中)20。
符号“f "表示一种运算,它对一些数的运算结果如下: (1)(1)0f =,(2)1f =,(3)2f =,(4)3f =,┄┄(2)1()22f=,1()33f =,1()44f =,1()55f =┄┄。
利用以上规律计算:1()2010(2010)ff -= 。
(2018永州)17。
对于任意大于0的实数x 、y ,满足:()222log log log x y x y ⋅=+,若2log21=,则2log 16=.(2018湘潭)16.(3分)阅读材料:若a b =N ,则b=log a N,称b 为以a 为底N 的对数,例如23=8,则log 28=log 223=3.根据材料填空:log 39= 2 .(2018达州)6.平面直角坐标系中,点P 的坐标为),(n m ,则向量OP 可以用点P 的坐标表示为),(n m OP =;已知),(111y x OA =,),(222y x OA =,若02121=+y y x x ,则1OA 与2OA 互相垂直。
2018年中考数学阅读理解专题复习题(人教版含答案)
阅读理解专题
吴健
阅读理解型问题一般字叙述较长,信息量较大,各种关系错综复杂,往往是先给一个材料,或介绍一个新的知识点,或给出针对某一种题目的解法,然后再给合条出题解决这类题的关键是要认真仔细地阅读给定的材料,弄清材料中隐含的数学知识、结论,或揭示的数学规律,或暗示的解题方法,然后展开联想,如何从题目给定的材料获得新信息、新知识、新方法进行迁移,建模应用,解决题目中提出的问题
一、新定义型
例1 对于实数a,b,定义运算“*”a*b=
例如4*2,因为4>2,所以4*2=42-4×2=8.若x1,x2是一元二次方程x2-5x+6=0的两个根,则x1*x2=_________________.分析用式法或因式分解法求出方程的两个根,然后利用新定义解之
解可以用式法求出方程x2-5x+6=0的两个根是2和3,可能是x1=2,x2=3,也可能是x1=3,x2=2,根据所给定义运算可知原题有两个答案3或-3.
本题容易忽视讨论思想,会少一种情况
评注本题需要学生先通过阅读掌握新定义式,再利用类似方法解决问题.考查了学生观察问题,分析问题,解决问题的能力.跟踪训练
1若定义f(a,b)=(-a,b),g(m,n)=(m,-n),例如,,则等于()
A.(2,-3) B.(-2,3) C.(2,3) D.(-2,-3)
2.对于实数x,我们规定【x】表示不大于x的最大整数,例如,,,若,则x的值可以是()
A.40 B.45 C.51 D.56。