主谓一致
一、主语和谓语必须在人称上一致
1.一般说来，主语和谓语必须在人称上一致，不受修饰语影响：
Eg: The results of exam show that you’ve all made good progress.
The questions raised by Mr. White are very important.
The building among the trees is our pubilc library.
2.如果主语表示一个抽象感念，一般用单数谓语
Eg: Growing flowers is no easy job.
That we have made amazing achievements is an undeniable fact.
3.当主语中包含and时，若指的是一个东西，可用单数谓语，若指的是两样东西，则需用
复数谓语。
Eg: The iron and steel indusry plays an important part in our national economy.
To try and fail is better than not to try all.
To mean to do something and to actually do something are different things.
4.如果主语是单数，尽管后面跟有with，togrther with，as well as, but except 等词引起的
短语，谓语仍用单数形式，因为这类短语多用作修饰语。
Eg: An iron and steel works, with several satellite factories, is being built in the city.
An expert, together with some assitants ,was sent there to help in the work.
二、主谓一致的原则
主谓一致是指一个句子的主语和谓语动词保持人称和数的一致。一个句子中主、谓一致，通常遵循三个基本原则：语法一致，即形式上一致；概念一致，即概念或意念上的一致；邻近一致，即指谓语动词的形式与邻近的名词一致。
1.语法一致原则
在通常情况下，一个句子的主语和谓语在语法形式上保持一致，即主语为单数形式，谓语动词取单数形式；主语为复数形式，谓语动词取复数形式。
This exercise on English idioms is not easy.
The visitors are interested in The Great Wall.
The man with many students around him is a professor.
2.概念一致原则
(1)主语是抽象概念、短语或从句，谓语用单数形式。
To tell lies is wrong.
How this happened is not clear to anyone.
注：用what或which引导的主语从句或简单句中的数的概念取决于它所代表的事物。Which is your seat?
Which are your seat?
What she did is not yet know.
What they gave me as reward are some books.
(2)两个或两个以上的主语用and 和both连接时，谓语动词用复数形式。
(3)如果and所连接的主语指同一个人，或者同一样东西，谓语动词用单数形式。
3.邻近一致原则
由not only …but also, neither…nor, either…or, or 连接的并列主语，其谓语的数与邻近的主语保持一致。
Not only the students but also the teacher is enjoying the film.
Neither he or I am mistaken.
Either he or you are to go there.
Are you or he right?
三、主谓一致的常见情况
1．单数名词由and连接
两个或两个以上由and连接起来并列做主语时，谓语动词用复数。
2. and连接的两个名词表示同一个人或物时，谓语动词用单数。
All work and no play makes Jack a dull boy. 只工作不玩耍，聪明孩子也变傻。
3. toursers等做主语
由两个相同部分连接成一体的表示衣物或工具等的复数名词，trousers, shoes, glasses, chopsticks等单独做主语时，谓语动词一般用复数；单如果与“a pair of”等表示数量单位的短语一起构成主语时，谓语动词则由两次的单复数来确定。
My trousers are on the bed.
A pair of trousers is on the bed.
Two pairs of trousers are on the bed.
4. 由介词、介词词组和某些连接词的两个并列名词或代词做主语，如as well as, as much as, rather than, no less than, together with ,more than, along with, besides, including, in addition to, not …, with, except, but, like等，谓语动词应与前面真正的主语保持一致。
I together with my parents am going to visit uncle Smith.
A library with five thousand books ____ by the nation as a gift.
A. is offered
B. has offered
C. are offered
D. have offered
No one but Jone and Jim was there yesterday.
5. 不定代词none以及由“none/either/neither +of +复数名词（或代词）”构成的短语作主语时，谓语动词单复数均可，着取决于说话人的侧重意义。
None knew when that was. (强调所有人)
None is so good as he. （强调每一个人）
Neither of them have replied.（强调他们两个都没有答复）
Neither of them had replied. （强调他们两个谁也没有答复）
6. 数词作主语时，谓语用单数，但在四则运算中，谓语单复数均可。
Ten is a round number.
Ten times five is/are fifty.
7.“分数（百分数）+ of + 名词”作主语时，谓语动词的数依据of 后的名词的数而定。
8. 表示部分概念或不定数量的名词代词作主语，如half of,most of, the rest of , the remineder of, lots of.plenty of等，谓语动词的数依of 后的名词的数而定。
9. all, any,some 作主语，谓语的数应根据所指的具体事物而定。
All are present.
All that can be done has been done.
10. Each 修饰名词作主语，谓语动词用单数。但each若位于复数主语后或句末作同位语，谓语用复数。
Each student has a dictionary.
Each of the students has a dictionary.
The students each have a dictionary.
The students have a dictionary each.
11. news, maths, physics 等名词虽然是复数形式，但表示单一概念作主语时，谓语动词用单
