主谓一致是指主语与谓语在数上要一致。把握主谓一致问题，考生主要解决的是对不同结构的主语单复数的认定，进而选择适当的谓语。解决主谓一致主要遵循三个原则：
语法一致原则
意义一致原则
就近一致原则
很多情况下应该综合利用这三个原则来处理主谓一致，在不同情况下可能应用三个原则中的不同原则，具体应用哪种原则应该视具体情况而定。总结如下：
一.谓语动词用单数的情况
1.动名词短语、不定式短语、名词性从句做主语，谓语用单数。如：
Buying clothes is often a time-consuming job because those clothes that a person likes are rarely the cones that fit him or her.
(1987年考研题)
To understand the situation completely requires more thought than has been given thus far.
2.表示时间、距离、金额、重量、面积、体积、容积等度量的名词短语做主语时，谓语用单数。
Two weeks was too long
Five times five makes twenty five
3.一般用and连接的两个单词或短语做主语时候，谓语用复数，但是下面用and连接的主语表示一个概念，谓语用单数：
law and order 法制 soap and water 肥皂水
a cup and saucer 茶杯碟子 fork and knife 刀叉
the needle and thread 针线 trial and error 反复尝试，不断摸索
horse and carriage 马车 time and tide 岁月
bread and butter 奶油面包 the ebb and flow 盛衰，潮涨潮落
如： If law and order not preserved, neither the citizen nor his property is safe.
A. is B. are C. was d. were
答案：A。
4.表示学科和某些疾病名称的名词是复数形式，作主语时候谓语动词用单数形式
Linguistics is a branch of study on human language.
5.有些名词形式上是复数，意义上是单数，根据意义一致原则动词用单数
The chaos was stopped by the police
The news is a great encouragement to us
A series of debates between the lectures was scheduled for the next weekend.
6.用and 连接的成份表示一个单一概念时候，动词谓语用单数形式
Bread and butter is our daily food
Time and tide waits for no man
二. 谓语用复数情况
1. 由and, both …and, 连接的并列主语，和both ,a few, many ,several 等修饰语后面谓语动词通常用复数形式。
Few people know he and I were classmates when
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