2016职称英语卫生类语法之主谓一致：

以单数名词或代词、动词不定式短语、动名词短语或从句作主语时，谓语动词一般用单数形式;主语为复数时，谓语动词用复数形式。如：His father is working on the farm./ To study English well is not easy./ What he said is very important for us all./ The children were in the classroom two hours ago./ Reading in the sun is bad for your eyes.

注意：由what引导的主语从句，后面的谓语动词多数情况用单数形式，但若表语是复数或what从句是一个带有复数意义的并列结构时，主句的谓语动词用复数形式。如：What I bought were three English books./ What I say and do is (are) helpful to you.