１）主语是一个抽象概念（包括不定式、动名词和名词性从句作主语），谓语动词用单数。
２）如果主语是单数，尽管后面跟有：with , together with , as well as , no less than, rather than ,
like , but , besides , except , as much as, including , along with ...等引起的短语，谓语动词仍然用单数。
３）each , some , any , no , every 构成的复合代词；one of +复数名词 , many a , more than one ( a )
等所修饰的词作主语，它们的谓语都用单数。
４） people , police, cattle 等词作主语通常用复数。
