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：
1) The kind of books an author writes depends on the kind of man who he is.
2) Some new types of cars are now on show.
3)These kind of recorders are good.
(8)由one and a half + 复数名词作主语时，谓语动词视名词的单复数形式而定。例如：
One and a half apples is left on the plate.
(9) 由the majority of + 名词作主语时，谓语动词视名词的单复数形式而定。例如：
1) The majority of the damage is easy to repair.
2) The majority of criminals are non-violent.
（10）plenty of, half of, a lot of, lots of, heaps of, loads of, scads of等 + 可数与不可数名词作主语时，不可数名词的谓语只用单数，可数名词的谓语视可数名词的单复数而定。例如：
1）Half of this building is to be completed by spring.
2）Half of the buildings have been painted completely.
3）There is plenty of water in the pail.
4）There are plenty of eggs in the box.
5）There is loads of milk on the farm.
6）There are loads of big red apples on the ground.
注：当名词前有其他量词修饰时，谓语动词的单复数形式通常取决于量词。例如：
1）Row upon row of soldiers is marching towards us on the field.
2）A body of volunteers has been organized to aid the helpless in their struggle for survival.
（11）由all of, most of, a lot of, some of, none of, plenty of , the rest 等 + 名词作主语时，谓语动词的单数形式应与名词一致。例如：
1）None of the books satisfy the students.
2）None of this meat is fit to eat.
3）All of the research work was designed by the chief engineer.
4）All of the students are against the plan for an outing at this time of the term.
（12）由more than one (或more than one + 单数名词)，many a + 单数名词作主语，谓语动词要用单数形式。例如：
1）More than one student has passed the examination.
2）Many a boy learns to swim before he can read.
注：如果more than后面是复数名词，则谓语动词要用复数。
例如：More than two hundred students have attended the lecture.
（13）quantity of + 不可数名词，谓语动词用单数形式; quantities of + 可数与不可数名词，谓语动词用复数形式。例如：
1）Great quantities of milk are needed in this city.
2）There is a large quantity of milk.
（14）如果名词词组中心词是“分数或百分数 + of + 名词”，谓语动词的单、复数形式取决于of后的名词或代词的单、复数形式。例如：
1）Over three-quarters of the swampland has been reclaimed.
2）Two-thirds of the people present are against the plan.
（15）定语从句谓语动词的单复数形式应与先行词一致。例如：
1）He is one of the men who were chosen to represent the group.
2）“Keep cool” is the first of the rules that are to be remembered in an accident.
注：当one之前有the only等限定词修饰时，定语从句的谓语动词用单数形式。例如：
He is the only one of those boys who is willing to take on another assignment.
2.概念一致（语言内容上一致）
（1）有些集合名词如crowd, family, team, orchestra（管弦乐队）, group, government, committee, class, school, union, firm, staff, public等，它们作主语时，谓语动词的数要根据语言内容而定。如果它们作为一个集体单位时，动词用单数形式，如就其中的各个成员来说，则谓语用复数形式。例如：
1）His family is going to move.
2）His family are very well.
3）The public is / are requested not to leave litter in the park.
注：如这类词后跟有定语从句时，定语从句的谓语动词也遵循概念一致的原则，强调具体成员时，谓语动词用复数，关系代词用who; 强调整体时，谓语动词用单数，关系代词用which。例如：
1）The government who were responsible for this event attempted to find a solution.
2）The government which was responsible for this event attempted to find a solution.
(2)有些表示总称意义的名词，形式上是单数，而意义上却是复数，谓语动词要用复数形式，如people, police, militia, cattle, poultry（家禽）等。例如：
1）Cattle were allowed to graze on the village common.
2）The police are searching for a tall dark man with a beard.
(3)有些名词形式上是复数，而意义上却是单数。如news, means, works.还有许多以ics结尾的学科名称，如economics, physics, mechanics, politics等，它们作主语时，谓语动词要用单数形式。例如：
1）Politics is a complicated business.
2）Here is the news.
(4)用and连接的单数主语，前面有each, every, many a, no等修饰时，谓语动词要用单数形式。复数主语与each连用时，应不受each的影响，谓语动词仍用复数形式。例如：
1) Each pen and each paper is found in its place.
2) Every boy and girl is treated in the same way.
3) Many a boy and many a girl has seen it.
4) The old workers and the young each have their own tools.
(5)表示重量、度量、衡量、价值的复数名词作主语，谓语动词常用单数形式。例如：
1) Twenty miles is a long way to walk.
2) Three pints isn’t enough to get me drunk.
(6)国家、单位和书报的名称，作为一个单一的概念，其谓语动词要用单数形式。例如：
1）War and Peace is the longest book I’ve read.
2）General Motors has recently closed down a plant. (通用汽车公司最近关闭了一家工厂。)
（8）the +形容词作主语时，如主语指的是一类人，谓语动词用复数形式；如果指的是单个人或抽象概念，谓语动词用单数形式。例如：
1) The blind are taught trades in special schools.
2) The departed was a good friend of his.
3.毗邻一致（就近原则）
(1)由连词or, neither…or, either…or, not only … also, nor等连接的并列主语，谓语动词的单复数形式按毗邻一致的原则，与贴近它的主语一致。例如：
1) He or you have taken my pen.
2) Either you or he is no telling the truth.
3) Not only the switches but also the old wiring has been changed.
(2)在there be 的结构中，谓语动词的单复数形式一般也采取就近原则。例如：
1)There is a desk and four benches in the office.
2)There are two chairs and a desk in the office.
二、指代一致
指代一致是指句中的代词应该在人称、数、性等方面与所指的词保持一致。
1.人称一致
(1)当代词指代名词或另一个代词时，须在人称上与所指代的词保持一致。例如：
1）I recognized one of the girls, but I didn’t speak to her.
2) That woman said that she was over fifty.
3) They asked whom they should apply to.
(2)当代词指代集合名词时，用单数人称代词强调整体，用复数人称代词强调个人。例如：
1) The committee have discussed their report on the disaster.
2) The audience are raising their hands to signify their approval.
(3)当everyone, everybody, no one, nobody, anyone, anybody, someone, somebody等作主语时，相应的代词一般采用单数形式。例如：
1) If anyone calls, tell him I’ll be back later.
2) Everyone thinks he is the center of universe.
注：在非正式文体中，特别是在会话体里，常用代词的复数形式是为了故意不具体说出所指的那个人的性别。例如：
1) Has anybody brought their camera?
2) No one could blamed themselves.
(4)由neither … nor, not only … but also, either … or, not … but, or等连结的并列主语，其后的附加疑问部分主语用复数代词。例如：
1) Neither you nor I am wrong, are we?
2) Both Tom and Jack came, didn’t they?
2.性、数、格一致
(1)代词的性一般仅限于第三人称。例如：
1) China will always do what she has promised to do.
2) The boy stood at the door with his hat in his hand.
(2) 当or或nor连接阳性名词或阴性名词时，代词一般和近者保持一致。例如：
1) Neither John nor Mary has got what she wanted.
2) If you should see Mary or Thomas, tell him the news.
(3)单数名词由and连接时，相应的代词一般用复数形式。例如：
1) Food and rent are more expensive than they used to be.
2) Jim and Mary spoke on the subject as if they were experts.
3.应注意的问题
(1)当句子的主语是one, 并要在句子中多次出现时，一般用第三人称单数代词来代替后面将出现的one或one’s;当one在句子中泛指人时，在反意疑问句中也可用you来代替。例如：
1) One should never blame his friends when he friends when he finds himself in trouble.
2) One can’t be too careful, can you (one)?
