主谓一致是指：
1） 语法形式上要一致，即单复数形式与谓语要一致。
2） 意义上要一致，即主语意义上的单复数要与谓语的单复数形式一致。
3） 就近原则，即谓语动词的单复形式取决于最靠近它的词语，
一般来说，不可数名词用动词单数，可数名词复数用动词复数。
There is much water in the thermos.
但当不可数名词前有表示数量的复数名词时，谓语动词用复数形式。
Ten thousand tons of coal were produced last year.
1 并列结构作主语时谓语用复数
Reading and writing are very important.
注意： 当主语由and连结时，如果它表示一个单一的概念，即指同一人或同一物时，谓语动词用单数，and 此时连接的两个词前只有一个冠词。
The iron and steel industry is very important to our life.
典型例题
The League secretary and monitor ___ asked to make a speech at the meeting.
A. is B. was C. are D. were
答案B. 注： 先从时态上考虑。这是过去发生的事情应用过去时，先排除A.，C.。本题易误选D，因为The League secretary and monitor 好象是两个人，但仔细辨别， monitor 前没有the，在英语中，当一人兼数职时只在第一个职务前加定冠词。后面的职务用and 相连。这样本题主语为一个人，所以应选B。
2 主谓一致中的靠近原则
1）当there be 句型的主语是一系列事物时，谓语应与最邻近的主语保持一致。
There is a pen, a knife and several books on the desk..
There are twenty boy-students and twenty-three girl-students in the class.
2）当either… or… 与neither… nor， 连接两个主语时，谓语动词与最邻近的主语保持一致。 如果句子是由here, there引导，而主语又不止一个时，谓语通常也和最邻近的主语一致。
Either you or she is to go.
Here is a pen, a few envelops and some paper for you.
3 谓语动词与前面的主语一致
当主语后面跟有with, together with, like, except, but, no less than, as well as 等词引起的短语时，谓语动词与前面的主语一致。
The teacher together with some students is visiting the factory.
He as well as I wants to go boating.