中考英语 (动词不定式)语法讲解 专项练习

上海中考英语专项练习非谓语动词（中考英语语法专项复习--非谓语动词）非谓语动词一、定义不充当句子谓语的动词叫做非谓语动词。

它们不受主语限制，无时态与语态变化，又称非限定性动词。

二、形式1. 动词不定式（to do sth. ）2. 动名词（v. -ing）3.分词现在分词（v. -ing)过去分词（v. -ed或不规则变化）此外，不定式可以与疑问词连用, 用作主语、宾语、表语等。

①I can’t decide which one to buy.我不能决定该买哪一件。

（作宾语）② When to start hasn’t been discussed.什么时候开始还没有被讨论。

（作主语）【温馨提示】(1)help后接不定式时可以省略to；(2)有些动词后接不定式时通常省略to：feel, hear, see, watch, notice, let, make, have （简记为一感一听三看三让）。

上述动词变为被动语态后，其后的不定式必须补上“to”。

①Tom helped his brother (to) learn to swim.汤姆帮他的弟弟学习游泳。

变为被动语态：His brother was helped to learn to swim by Tom.②We often hear Jack sing English songs.我们常听见杰克唱英文歌。

变为被动语态：Jack is often heard to sing English songs.【巧学妙记】只能跟不定式作宾语的动词决心学会有希望（decide, determine, learn, wish, hope）,同意计划莫假装(agree, plan, pretend),胆敢拒绝会失败（dare, refuse, fail）,准备设法来帮忙(prepare, try, manage, help),提供请求负担起(offer, beg, demand, afford),答应安排理应当（promise, arrange, be supposed）,以上后跟不定式，劝君牢记永不忘。

广州中考英语专项-动词不定式不定式在句子中可做主语、宾语、表语、定语、状语和宾语补语。

1) 不定式做主语一般表示具体的某次动作。

【例如】To complete a building like that in one year was quite adifficult task.当主语较长，谓语较短时，常用it做形式主语，而将不定式放到谓语的后面。

【例如】It is important for modern young people to master at leasttwo foreign languages.It做形式主语，不定式放在谓语动词之后常用于下列结构中：a)It is＋形容词(easy, important, difficult, foolish, inconvenient,unnecessary, right, wrong...)＋( for/of sb.)＋不定式【例如】It is essential to reserve a table in advance of ChristmasEve.It is hard to put my hopes into words.It is not easy to catch fish with your hands only.It is important for us young people to learn English and master it.b)It is＋名词(a pleasure, a pity, a pleasant thing, one's duty, anhonor, a shame,a crime, no easy job...)＋不定式It is a sheer waste of time to read that kind of trash.It is a pity to have to go without her.It is a glorious death to die for the people.c)It takes (sb.) some time (hours, months, days, a lot of time,patience...)＋不定式It takes me three hours to learn English each day.It took them half the night to get home in the snow.2)不定式作表语不定式作表语常表示将来的动作，主语常常是表示意向、打算、计划的词，如wish, idea, task, purpose, duty, job等。

动词不定式非谓语动词指的是在句中不能单独作谓语, 但保留动词的某些特征（如有自己的宾语或状语等）的动词形式。

非谓语包括动词不定式、现在分词、过去分词和动名词。

非谓语动词没有人称和数的变化, 但要遵循基本的时态语态规则, 在句中充当各种成分。

一、动词不定式基本构成形式 结构 例句肯定形式to+动词原形The teacher asked his students to finish their homeworkon time.老师让学生们按时完成作业。

否定形式 not to+动词原形Aunt Li often tells her son not to eat too much sugar. 李阿姨经告诫她的儿子不要吃太多的糖。

被动形式 to+be+过去分词He would like to be treated as a child. 他喜欢被当成孩子般看待。

注意: 动词不定式在一些感官动词（see, watch, hear 等）或使役动词（make, let, have 等）的后面, 做宾补时, 通常会省略to, 如:动词不定式知识精讲The boss made me work ten hours a day.=I was made to work ten hours a day by the boss.这个老板让我一天工作十个小时。

二、动词不定式的语法功能动词不定式在句子中可充当主语、表语、宾语、宾补、定语和状语（即除谓语之外的各种成分）。

1.不定式作主语1).动词不定式短语作句子主语时，视为单数，谓语动词用第三人称单数，如：To make work more efficient is our goal.让工作更有效率是我们的目标。

2).不定式短语作主语时, 为了考虑句子的平衡, 常用it作形式主语, 而将真正的不定式主语放在句子后面, 结构为: It+is/ was+adj.(+for sb.)+动词不定式, 如上一句话也可写成:It’s our goal to make work efficient.我们的目标是让工作更有效率。

初中英语动词不定式用法动词不定式是由“不定式符号动词原形”构成的一种非谓语动词结构。

有些动词不定式不带，动词不定式可以作句子的主语、表语、宾语、定语、补语、状语或单独使用。

不定式保留动词的某些特性，可以有自己的宾语、状语等。

动词不定式和它后面的宾语、状语等一起构成短语，叫作不定式短语。

一、用作主语直接把动词不定式置于句首的情况不多，多数情况用作形式主语，把真正的主语——动词不定式置于句末，特别是不定式短语较长时。

动词不定式作主语，谓语动词用第三人称单数形式。

带疑问词的不定式短语作主语常置于句首，复合不定式结构作主语常置于句末。

如：1. I t .2 .3 .4 .(眼见为实；百闻不如一见)二、用作表语动词不定式作表语，常说明主语的内容、性质、特征。

如：1 .2 .三、用作宾语1.可以接带的动词不定式作宾语的动词主要有：要求选择同意(, , )，期望决定学习(, , , )，宁可假装知道(, , )，希望想要愿意(, , / )。

如：1) .2) .3) Mexico.2.动词, , , , , ...，介词结构...可用疑问词带的不定式短语作宾语，但后面的不定式不带。

如：1)2) .3.动词, , , 等后面，可以用作形式宾语代替真正的宾语——动词不定式，句子结构是 / / / ... . / ...。

如：I .4.既可接动词不定式又可接形式作宾语，意思差别不太大的动词有, , , 等。

一般说来，动词不定式表一次、数次的具体动作、将来动作或动作的全过程，形式表习惯性的连续动作。

但是这种区别并不很严格，特别是美国英语，即使是习惯性的动作也可以用动词不定式。

如：1) I .2) I .用了进行时态，后面只接不定式作宾语，表示事情刚开始，还要继续下去。

3) I .感知动词, , 等一般不用进行时态。

5.后接动词不定式或形式作宾语，意思差别较大的动词有, 等。

后接不定式作宾语，表动作尚未发生；后接形式作宾语，表动作已经发生。

初中英语动词不定式练习题及解析1. 阅读理解> Passage:Passage:>c) to joind) joininge) to improvef) improveg) to achieveh) achieving解析：- 第二空应选 c) to join。

根据句子结构“He hopes + tojoin/joining” 可知应选 c) to join。

to join 是不定式形式，表示希望加入某个篮球队。

- 第三空应选 e) to improve。

根据句子结构“always encourage + to improve/improve” 可知应选 e) to improve。

to improve 是不定式形式，表示鼓励提高某人的技能。

- 第四空应选 g) to achieve。

根据句子结构“help him + to achieve/achieving” 可知应选 g) to achieve。

to achieve 是不定式形式，表示帮助实现某人的目标。

2. 句子转换Change the sentences below by rewriting the underlined phrases using the verb in brackets:> Example:Example:>> Tom wants to visit his grandparents. (see)>> Tom wants [to see] his grandparents.b) We plan to go camping next weekend. (do)c) He hopes to find a new job after graduation. (get)d) They decided to buy a new car for their family. (purchase) 解析：b) We plan [to do] camping next weekend.c) He hopes [to get] a new job after graduation.d) They decided [to purchase] a new car for their family.3. 完形填空> Passage:Passage:>a) to joinb) joiningc) to tryd) tryinge) aref) is解析：- 第一空应选 a) to join。

2019-2020学年中考英语专题讲练动词不定式（含解析）知识精讲非谓语动词指的是在句中不能单独作谓语，但保留动词的某些特征（如有自己的宾语或状语等）的动词形式。

非谓语包括动词不定式、现在分词、过去分词和动名词。

非谓语动词没有人称和数的变化，但要遵循基本的时态语态规则，在句中充当各种成分。

一、动词不定式基本构成注意：动词不定式在一些感官动词（see, watch, hear等）或使役动词（make, let, have 等）的后面，做宾补时，通常会省略to，如：The boss made me work ten hours a day.=I was made to work ten hours a day by the boss.这个老板让我一天工作十个小时。

二、动词不定式的语法功能动词不定式在句子中可充当主语、表语、宾语、宾补、定语和状语（即除谓语之外的各种成分）。

1. 不定式作主语1). 动词不定式短语作句子主语时，视为单数，谓语动词用第三人称单数，如：To make work more efficient is our goal.让工作更有效率是我们的目标。

2). 不定式短语作主语时，为了考虑句子的平衡，常用it作形式主语，而将真正的不定式主语放在句子后面，结构为：It+is/ was+adj. (+for sb.)+动词不定式，如上一句话也可写成：It’s our goal to make work efficient.我们的目标是让工作更有效率。

It’s very important for us to learn English well.学好英语对于我们来说很重要。

2. 动词不定式作宾语1). 动词不定式跟在及物动词后作宾语，这种形式非常常见，就是我们平时积累的一些动词后面跟to do形式，如：I have decided to study hard.我已经决定要刻苦学习。

常见的这类动词有：begin, choose, continue, decide, expect, fail, forget, hate, help, hope, learn, manage, mean, need, offer, plan, prefer, pretend, promise, refuse, try, want, wish, determine, afford, agree, start, like等。

动词不定式动词不定式不能做谓语，一种非谓语动词结构。

有些动词不定式不带to，动词不定式可以作句子的主语、表语、宾语、定语、补语、状语或单独使用。

一、结构主动式：to+动词原形；否定形式：not to+动词原形被动式：to be+动词的过去分词二、用法1、作主语动词不定式作主语，谓语动词用第三人称单数形式。

(1)常用it作形式主语；真正的主语：“动词不定式”①It＋be＋形容词＋for sb.＋to do sth. (adj.为necessary，important等)It is easy for us to learn English.②It＋be＋形容词＋of sb.＋to do sth. (adj.为人的品质，clever，good，kind等)“It is stupid of you to write down everything”，the teacher says.③It＋be＋名词＋to do sth.It's our duty to take good care of the old.④It seems(appears)＋形容词＋to do sth.It seemed impossible to save money.(2)把不定式置于句首。

如：To get there by bike will take us half an hour.(3)带疑问词的不定式短语作主语How to solve the problem is hard for him.2、作表语动词不定式作表语，常说明主语的内容、性质、特征，通常放在连系动词（主要是be动词）后。

1.The best way to improve your English is to join an English club.2.The first thing is to greet the teacher.注意：不定式作表语表示具体动作或将来动作；动名词作表语表示抽象的一般行为。

学生姓名:上课时间:动词不定式一. 定义:动词不定式是非谓语动词的一种,它没有人称和数的变化,在句子中不能独立作谓语,但它仍保持动词的特点,既可以有自己的宾语和状语。

同时动词不定式又具有名词、形容词、副词的特征,在句中可以作主语、表语、宾语、宾语补足语、定语和状语。

二. 动词不定式的构成:to+动词原形三. 动词不定式作宾语1、作宾语She wanted to become an actor.后面能接不定式作宾语的动词有:agree, ask, choose, decide, forget, hope, learn, want, wish, would like等。

We hope to get there before dark. 我们希望天黑以前到那儿。

The girl decided to do it herself. 那个姑娘决定自己做那件事。

动词不定式作宾语的注意事项(2点1. 有些动词既可跟不定式作宾语,也可跟动名词作宾语,但含义不同:remember to do 记住要做某事remember doing 记得曾经做过某事forget to do忘记要做某事forget doing 忘记曾经做过某事stop to do 停下来去做某事stop doing 停止做某事go on to do 继续做另一件事go on doing 继续做原来在做的事like doing 喜欢做……(与生俱来的,一般不容易改变like to do 喜欢做……(后天形成的,很容易改变I remember seeing you somewhere before.我记得以前在哪儿见过你。

Please remember to turn off the light when you leave.离开时请记得关好灯。

2. 不定式作宾语时,如带有宾语补足语,则要把不定式放到后面,用it作形式宾语,构成“主语+动词+it+宾补(形容词、名词+不定式”结构。

中考英语不定式和动名词讲解练习(总8页)--本页仅作为文档封面，使用时请直接删除即可----内页可以根据需求调整合适字体及大小--中考英语不定式和动名词讲解练习不定式一：动词不定式的构成不定式的基本形式：to +动词原形，有时不用to。

这里的to是不定式的符号，本身无意义，否定形式在前面加not.二：动词不定式的句法功能1) 主语：不定式作主语时，常用it 作形式主语，把不定式放在后面。

It is not easy for us to speak English.2) 表语：多数情况下，不定式作主语可转化为作表语。

My work is to clean the room everyday.= To clean the room everyday is my work.3) 宾语：不定式只能做某些动词的宾语，一般不做介词的宾语（but，except除外）。

----what sports does he like to play?----He likes to play basketball.4) 宾补：在make, let, see, hear, watch等使役动词，感官动词后，不定式省略toShe asked me not to speak Chinese in the English class.5).定语：不定式作定语，要放在所修饰的词后面。

Have you got anything to say?6).状语：不定式作状语，其逻辑主语要和主语一致。

I’m sorry to trouble you.(表原因)题组训练：用所给词的正确形式填空1. I hope _______ (find) a good job in a foreign company after I graduate from school.2. He found it hard to ____________________ (catch up with) his classmates.3. Mother asks me ________________ (not play) computer games before finishing my homework.4. All the children like Mr. White very much because he often makes them___________ (laugh).5. Let him ________ (have) a rest. I think he must be tried after the long walk.6. We have two rooms _______ (live) in, but I can’t decide which one ______ (choose).动词不定式专题练习1. This company was the first ____ portable radios as well as cassette tape recorders in the world.A. producingB. to produceC. having producedD. produced2. The purpose of new technology is to make life easier, ____it more difficult.A .not making B. not make C .not to make D. nor to make3. Helen had to shout ______above the sound of the music.A .making herself hear B. to make herself hearC. making herself heard D .to make herself heard4. I don’t know whether you happen_______, but I am going to study in the this September.A .to be heard. B. to be bearing C .to hear D .to have heard5. The news reporters hurried to the airport, only ______the film stars had left.A .to tellB .to be toldC .tellingD .told6. You were silly not _______your car.A. to lockB. to have lockedC. lockingD. having locked7. The teacher asked us ______so much noise.A .don’t make B. not make C. not making D .not to make8. An army spokesman stressed that all the soldiers had been ordered _____clear warnings before firing any shots.A .to issue B. being issued C. to have issued D. to be issued9. I’d rather have a room of my own, however small it is, than_______ a room with someone else.A. to shareB. to have sharedC. shareD. sharing10. The bank is reported in the local newspaper_________ in broad daylight yesterday.A. robbedB. to have been robbedC. being robbedD. having been robbed11. A number of paintings in the castle are believed ________in a fire.A. being destroyedB. having been destroyedC. to be destroyedD. to have been destroyed12. The meeting _______ next week is sure to be a great success.A. to take placeB. to be taken placeC. to have taken placeD. being taken place13. As a result of my laziness, I failed ________ my work in time.A. and finishedB. to finishC. and finishingD. to finished14. I am sorry ______ written you a letter at the time.A. to have notB. to not haveC. not to haveD. not having15. Will you lend him a magazine _________A. to be readB. for readingC. to readD. he read16. He could do nothing but _______for the bus _________.A. wait, to comeB. wait; comeC. waiting; comingD. waited; came17 .It is a problem that doesn't need ________ right now.A. to solveB. solvingC. being solvedD. to be solving18. There’s a man at the reception desk who seems very angry an d I think he means _______ trouble.A. makingB. to makeC. to have madeD. having made19. I remember _______him _______the bike needed __________.A. hearing, saying, to repairB. to hear, say, to repairC. hearing, say, repairingD. to hear, saying, to be repaired20. --- You should have thanked her before you left.--- I meant _________, but when I was leaving I couldn’t find her anywhere.A. to doB. toC. doingD. doing so21. Robert is said to __________ abroad, but I don’t know what country he studi ed in.A. to have studiedB. to study B. to be studying D. to have been studying22. I’m gong to Xi’an next week. Have you anything __________ to your parents?A. to takeB. to be takenC. to be bought toD. to buy23. when are they __________ in their plan?A. handB. handedC. to handD. give24. In such dry weather, the flowers will have to be watered if they _____________.A. have survivedB. are to surviveC. would survivedD. will survive25. When we hurried to the station, there happened ________ no bus at that time.A. to haveB. to beC. havingD. being26. I lost my way in complete darkness and, _________ matters worse, it began to rain.A. madeB. having madeC. makingD. to make27. At ________ time does the salesgirl get up late in the morning, though she isalways too busy _________ a good rest.A. no, to takeB. no, takingC. any, to takeD. one, taking28. --Are you a student?--No, but I used _________.A. to beB. to wasC. to doD. to be a29. I stopped to listen, and my son seemed _________ himself _________ in the living room.A. to enjoy, to shutB. to be enjoying, shuttingC. to be enjoying, shutD. to have enjoyed, having shut30. With a lot of difficult problems _________, the newly-elected president is having a hard time.A. settledB. settlingC. to settleD. being settled31. We’re leaving at six o’clock, and hope _________ most of the journey by lunch time.A. to doB. to have doneC. to makeD. to have made32. The study of the wild world may help to make the world easier _________.A. understoodB. to be understoodC. to understandD. understand33. Who will you get __________ the project for us?A. designB. to designC. designedD. designing34. It is said in Australia there is more land than the government know __________.A. it what to do withB. what to do it withC. what to do with itD. to do what with it35. We are not allowed __________ outdoors with some other children.A. playingB. to be playingC. to playD. be playing36. Allen had to call a taxi because the box was _________ to carry all the way home.A. much too heavyB. too much heavyC. heavy too muchD. too heavy much37. She feels so strongly that each of us should have a role __________in makingthe earth a better place to live in.A. to have playedB. to playC. to be playedD. to be playing38. When I handed the report to John, he said that George was the person_________.A. to sendB. for sending itC. to send it toD. for sending it to39. Do let your mother know all the truth, she appears _________ everything.A. to tellB. to be toldC. to be tellingD. to have been told40. There are five pairs ___________, but I’m at a loss which to buy.A. to be chosenB. to choose fromC. to chooseD. for choosing41. The problem is _________ difficult for us __________.A. so; work outB. very too; to be worked outC. rather too, to work outD. quite too, to work it out42. ---Where should I _________ my application?---The personnel office is the place __________.A. send; to send itB. send for; to send it toC. send for; for sending itD. send; to send it to43. I’ve worked with children before, so I know what ___________ in my new job.A. expectedB. to expectC. expectsD. to be expecting44. I feel it is your husband who ___________ for the spoiled child.A. is to blameB. is going to blameC. is to be blamedD. should blame45. Can you imagine the questions I had __________ our teacher?A. askedB. to askC. askingD. ask46. Who did you _________ the wall yesterday?A. have paintedB. have paintC. have to paintD. have painting47. ---What’s the matter with John?---He didn’t pass the test but he still ___________.A. hopes soB. hopes toC. hope itD. hope that48. Much attention should be paid ____________ people’s living conditions.A. in improvingB. to improveC. improvingD. to improving49. ___________ that evening was due to his ill health.A. He failed to comeB. That he failed to comingC. His failure to comeD. His failure in coming50. I would love _______ to the party last night but I had to work extra hours to finish a report.A. to goB. to have goneC. goingD. having gone51. My family considers ________ a computer, which is considered ________ a great help in our work and study.A. to buy; to beB. buying; beingC. to buy; beingD. buying; to be52. With the plane _________ in ten minutes, all the passengers on board were asked to turn off their mobile phones.A. taken offB. taking offC. to take offD. would take off53. Thank you for all the trouble you’ve taken _________ me.A. to helpB. with to helpC. in helpingD. of helping54. He is believed ________ the college exam, for he is now studying very hard now.A. to passB. to have passedC. passD. that he can passWill you have anybody _________ the flowers?---- Yes, I’ll have the flowers _________.A. plant, plantedB. to plant, plantedC. plant; to be plantedD. to plant , plant56. They are looking forward with hope________ from you soon.A. to hearingB. of hearingC. hearingD. to hear57. Busy translating a book, he couldn’t help _________ the article.A. writeB. writingC. wroteD. written58. Zhou Lan doesn’t have to be made__________. She always studies very hard.A. learnB. to learnC. learningD. learned59. ________this cake, you’ll need 2 eggs, 175 g sugar, and 175 g flour.A. Having made, B, Make C. To make D. Making60. I feel it an honor _________ to speak here.A. to be askedB. to askC. having askedD. asked1---10 BCDDB BDACB 11---20 DABCC ABBCB 21---30 ABCBB DAACC31-40 BCBCC ABCDB 41—50CDBAB BBDCB 51—60 DCAAA AABCA动名词一: 动名词的构成动名词由“动词原形+ing”构成二：动名词的句法功能1）动名词用作主语Saving is getting. 节约即增收。

初中英语语法（动词不定式）1．不定式的基本形式与结构动词不定式指通常由to加上动词原形(如to write) 所构成的一种非限定性动词形式，但在有些情况下to可以省略。

动词不定式有进行体和完成体(如上to be writing，to have written)，也有被动态(如to be written)，所有的主动词，不论是及物动词还是不及物动词，也不论是动作动词还是状态动词，都有不定式形式。

助动词除be和have外，没有不定式形式。

动词不定式在语法功能上可作主语、宾语、表语、定语和状语。

2．不定式的用法1)不定式结构作主语1.Te get contact with his family in Taiwan made him extremely happy since they separated more than 40 years ago．2.To finish that task in such a short time is really a challenge．在上述情况下，如果不定式较长，显得头重脚轻，则可由代词让作形式主语(形式主语it不可由that或this等其他代词代替)，而将不定式放到后面。

如：1.It made him extremely happy to get contact with his family in Taiwan since they separated more than 40 years ago．2.John admitted that it is always difficult for him to be on time．不定式结构所表示的动作是谁做的，即不定式的逻辑主语，通常可以通过for sb. to do sth. 结构表达：1.It is quite important for us to read good books during a general review．2.It is not difficult fot those talented students to pass the exam.在某些形容词(如careless，clever，considerate，foolish，good，impolite，kind，naughty，nice，silly，stupid等)作表语时，不定式后可以加of来引导出其逻辑主语：1.It is very kind of you to tell me the truth．2.It is stupid of him to do such a silly thing．2)不定式作宾语不定式作宾语有两种：一种是及物动词后直接跟带to的不定式，另一种是“及物动词+疑问词+带to的不定式。

期末复习之不定式一、单项选择1．Could you tell me how ________ things on the Internet?A．buy B．to buy C．to buying D．buying【答案】B【详解】句意：你能告诉我怎样在网上购物吗？考查非谓语动词。

疑问词+动词不定式作动词tell的宾语，所以此空应填动词不定式，故选B。

2．You must tell them ________, and then they will study better.A．how to study B．study C．where to study D．studying【答案】A【详解】句意：你必须告诉他们怎样学习，那他们就会学的更好。

考查固定用法。

根据tell sb to do sth表示“告诉某人做某事”可知，排除B和D；结合题干，此处也可以用“疑问词+不定式”作宾语，根据“...then they will study better.”可知教会如何学习，才会更好。

故选A。

3．Emm’s parents always tell her ________ food before washing hands.A．eat B．not eat C．don’t eat D．not to eat【答案】D【详解】句意：艾玛的父母总是告诉她洗手前不要吃东西。

考查不定式结构。

tell sb. not to do sth.“告诉某人不要做某事”。

故选D。

4．—I’m thinking about how ________ a report about A Lifelong Journey（《人世间》）.—Why not read some reviews first?A．to write B．writing C．writes D．wrote【答案】A【详解】句意：——我正在考虑如何写一篇关于《人世间》的报告。

中考动词不定式(to do)讲解+专练[附答案]在英语句子中,动词有两种。

一种是谓语动词,另一种是非谓语动词。

动词不定式就属于非谓语动词。

动词不定式没有人称、数和时态的变化。

不受主语人称和谓语动词的时态变化影响。

在句子中不能单独做谓语，但仍要保留动词的特点，既可以有自己的宾语和状语。

一.动词不定式的基本形式;不定式的基本形式是to+动词原形，to没有任何意义，不翻译。

不定式的否定形式在不定式前+not/never即可。

二.动词不定式的句法作用1.动词不定式作主语动词不定式可以用作句子中的主语，这时谓语动词要用单数。

Eg:To see is easy ，but to do is difficult.To ask him for help is necessary.To help poor people is our duty.★当动词不定式做主语时,如果带有宾语或状语,那么主语就会很长。

这时，常用it来代替不定式做形式主语,而将真正的主语---不定式,转移到谓语之后,以避免句子结构头重脚轻。

Eg:It is necessary to ask him for help.It is our duty to help poor people.It is not easy to master a foreign language.It took us two hours to get there by bike.★如果要说明不定式的动作是谁做的,不定式前要用for引起的短语。

常用结构是It be+adj+for sb+to do sth.翻译为“做某事对于某人来说是怎么样的？Eg:It is important for us to study English well.It is difficult for him to answer these questions.★如果某些表示人的品行的形容词,例kind,good,nice,wrong,careless,wise,foolish,polite,clever,right,unwise,stupid,thoughtful,rude,silly,impolite等等作表语时，不定式前要用of引起的短语。

概念:动词不定式由to+动词原形构成。

这里的to是不定式标志,没有词义。

不定式具有名词、形容词或副词的某些语法功能,又有动词的时态和语态的特点及作用。

可以做主语、宾语、宾语补足语、表语、定语、状语。

一、作主语动词不定式作主语时，句子的谓语动词常用单数，其位置有以下两种：(1）把不定式置于句首.如：To get there by bike will take us half an hour。

（2）用it作形式主语,把真正的主语不定式置于句后,常用于下列句式中.如：①It＋be＋名词＋to doIt's our duty to take good care of the old.②It takes sb+some time+to doHow long did it take you to finish the work?③It＋be＋形容词＋b＋to doIt is difficult for us to finish for swriting the composition in aquarter of an hour。

在句型③中,常用表示客观情况的形容词,如：easy，difficult，hard,important，possible，impossible，comfortable，necessary,better; the first，the next,the last,the best,too much，too little，not enough④It＋be＋形容词＋of sb＋to doIt is stupid of you to write down everything the teacher says.在句型④中,常用careless,clever，good,foolish,honest，kind，lazy，nice,right,silly,stupid,wise rude，clever,foolish，thoughtful, thoughtless（欠考虑的；不考虑的）,brave,considerate(考虑周到的)，selfish（自私的）等表示赞扬或批评的词。

动词不定式(to do)语法讲解动词不定式是由“to+动词原形”构成 (有时可以不带to)，其否定形式是“not to + 动词原形”。

它属于一种非谓语动词的形式,在句子中不能充当谓语,没有人称和数的变化,但它可以保留动词的性质,其本身可以带宾语或状语等附加成分（不定式和其附加成分称为不定式短语）。

动词不定式（短语）的句法功能非常广泛,在句中可作主语、宾语、补足语、表语、定语及状语等成分。

一、作主语（1）动词不定式作主语时,谓语动词常常用单数，例如：To do morning exercises is useful for our health. 做早操有利于我们的健康。

To sweep the floor is my duty every day. 每天打扫地板是我的责任。

把以上两句变为it作形式主语的句子：（2）如果动词不定式太长，常常用it 作形式主语,而将真正的主语——动词不定式后置，例如：To learn English well is important. 对我们来说,学好英语是重要的。

It’s important for us to learn English well．It took me half an hour to walk there．我走到那儿花了半小时的时间。

it不作形式主语：___________________________________________________________ 二、作宾语（1）能够接动词不定式作宾语的有ask, agree, beg, decide, determine，fail, hope, manage, offer, plan, prepare, pretend, promise, refuse, wish 及would like/love 等动词，但finish, enjoy, miss, appreciate, mind, advise, suggest 等动词后面通常只能接动名词（doing）作宾语，例如：I hope to visit this place again.我希望能再度访问此地。

语法：动词不定式动词不定动式是一种非谓语动词形式，它没有人称和数的转变，在句子中不能作谓语，但能够作除谓语之外的其它任何句子成份（主语、表语、宾语、宾语补足语、定语和状语）；动词不定式具出名词、形容词和副词的特点，同时还维持动词的某些特点，既能够有自己的宾语和状语，动词不定式和它的宾语和状语组成不定式短语。

一、组成：to do .否定式not to do二、常见时态：一样时to do 进行时to be doing 完成式to have done完成进行式to have been doing三、动词不定式在句子中的成份一、作句子的主语：现实中常用it 作形式主语，而把真正的主语动词不定式（或短语）后置。

比较以下句子To learn from your friends is important.=It is important to learn from your friends .To leave without saying goodbye is impolite.= It is impolite to leave without saying goodbye.To chat with Miss White is a pleasant thing.=It is a pleasant thing to chat with Miss White.To walk to school takes me ten minutes.=It takes me ten minutes to walk to school.句型总结It is + adj. + of sb. to do…= sb. is\are +adj. +todo…在以某些表示人的品质、特点等的形容词（如kind、good、nice、wrong、clever、right等）作表语时，不定式之前常加一个引发的短语，说明不定式指的是谁的情形（能够明白得为某人的好，坏，伶俐，愚蠢，对，错等等）。

中考英语动词不定式及其用法讲解+练习1.动词不定式的基本概念：动词不定式的基本形式是“to+动词原形”，有时可以不带to。

动词不定式没有人称和数的变化，在句中不能做谓语，但可以有自己的宾语和状语。

动词不定式跟它的宾语和状语构成了不定式短语，例如：to read the book, to speak at the meeting等。

2.动词不定式的用法：动词不定式具有名词，形容词和副词的特性，因此可在句中作主语，表语，宾语，宾语补足语，状语和定语。

句子用法：作主语：eg:1)To take part in sports is important.2)To see is to believe.动词不定式做主语时常常由it来代替它，做形式主语，而动词不定式放在句末。

eg: It’s great to see you again.It is important to learn English well.It was rewarding to take part in this exchange programmeIt will take us a month to go on study trip to New York.It is necessary for governments to control the population growth.做表语：eg：The best way is to pratice.My dream is either to be a diplomat or to be a teacher of English .A popular use of the computer is to send a e-mail.Her wish is to become a famous star.The best way is to read the play before you see it.做宾语：eg: We are talking about how to solve the problem.I think it not difficult to keep reading English every morning.做宾补：eg: We all expect him to win the contest.Our teacher told us to listen carefully in class.注意：感官动词，或使役动词+宾语+无to的不定式Is Jack in the library ?Maybe I saw him go out with some books just now.Let those in need understand that we will go all out to help them.做定语：Liu Yang is the Chinese woman astronaut to enter the space.You are the last one to win the price.In the future , human will have less work to do.Why don’t you go out to play Rose?I’m afraid I can’t . I have a lot of homework to do.做状语：动词不定式做状语可以修饰动词，一般在句中做原因，目的和结果状语，动词不定式做状语可单独放在句首，句中或句末。

动词不定式是一种非谓语动词的形式，没有人称和数的变化，在句中不能单独作谓语，但在句中可以作主语、表语、宾语、宾语补足语、定语和状语等。

to do not to do动词不定式的用法.1. 动词不定式作主语时，it(即动词不定式)放在句末。

To learn English well is important. = It is important to learn English well.It is+adj.+(for/of sb.)+to do sth.此处形容词表示事物性质，如important, useful, difficult 等。

It’s important for us to do sports every day 每天做运动对我们是重要的。

It is +adj.+ of sb. + to do sth. 此处形容词表示人的品质，如kind, nice, clever, friendly 等。

It’s very kind of you to help me. 你帮助我真是太好了。

It takes sb.+some time+to do sth.It took him two hours to do his homework yesterday. 昨天他花费两个小时做作业。

My dream is to be an engineer. 我的梦想是做一位工程师。

My work is to clean the room every day. 我的工作是每天打扫房间。

动词不定式常用在及物动词后，作宾语，其结构为。

常接动词不定式做宾语的动词有：decide,hope,wish,plan,learn,need,agree,choose,want, would like,What do you plan to do this Saturday? 这周六你打算做什么？He doesn’t need to clean his bedroom tonight. 他今晚不需要打扫房间。