一、主谓一致

主谓一致有许多原则，概括起来不外乎三种一致原则，即语法形式一致，概念一致（语言内容上一致），毗邻一致（谓语动词的单复数形式和紧位于其前的主语一致）。

1. 语法形式一致

（1）单数主语、单个动词不定式、动名词短语以及句子作主语，谓语动词要用单数形式。复数主语，用and或both…and连接的动词不定式短语、动名词短语以及主语从句作主语，谓语动词则用复数形式。例如：

1) The performance was very funny.

2) Serving the people is my great happiness.

3) Whether we’ll go depends on the weather.

4) Many natural materials are becoming scarce.

5) Both you and I are　students.

6) What I think and what I seek have been fairly reflected in my paper.

注1：在what 引导的主语从句中，如果主语补语是复数时，谓语动词用复数形式。例如：

What we have to learn are the pieces of language that produce inversion.

注2：修饰语对主语的数不起影响。例如：

The performance of the first three clowns was very funny.

（2）由as well as, with, along with, like, together with, rather than, except, but, including, accompanied by, plus, besides, in addition to, no less than 等引起的结构跟在主语后面，不能看作是并列主语，该主语不受这些词组引导的插入语的影响，主语如是单数，其谓语动词仍然用单数形式。例如：

1) My mother, as well as my father, has a key to the office.

2) The man together with his wife and children sits there watching TV.

3) His sister no less than you is wrong.

4) The reading course book, plus its reference books, is helpful to college students.

注：有时在with结构里，加上both之后，with就具有and含义。例如：

Grandpa Wang with his son, both looking very happy, are taking a walk in the park.

(3)有些代词只能指单数可数名词，当它们在句子中作主语时，尽管在意义上是多数，谓语动词仍要用单数形式。这类代词有either, neither, each, one, the other, another, somebody, someone, something, anyone, anything, anybody, everyone, everything, everybody, no one, nothing, nobody等。例如：

1) Neither likes the friends of the other. (两人都不喜欢对方的朋友。)

2) Everything around us is matter. (我们周围的所有东西都是物质。)

(4)在neither of与either of的结构里，一般语法书都认为谓语动词可用单数形式也可用复数形式，但在美国的TOEFL考试内要求用单数形式。例如：

1) Neither of them was in good health, but both worked very hard.

2) Has either of them been seen recently?

(5)当and连结的两个名词是指同一个人或同一件事，and后的名词前没有冠词，谓语动词应该用单数形式；在and后面的名词前有冠词，谓语就用复数形式。例如：

1)The bread and butter is served for breakfast. (早饭供应黄油面包。)

2)The bread and the butter are on sale. (正在出售黄油和面包。)

（6）当one of, a portion of, a series of, a species of, a chain of 结构作主语时，谓语动词要用单数形式。例如：

1)One of those students has passed the examination.

2)A series of pre-recorded tapes has been prepared for language laboratory use.

(7)form of, type of, kind of 结构的谓语视form, type与kind的单复数而定.these/those kind/type of后是复数名词，谓语动词用复数形式。例如：