饰成分之前的主语保持一致，也就是就远原则。

Our English teacher together with our classmates is playing a game.

我们英语老师正和同学们在做游戏。

【即学即练2】E-mail as well as telephones______(be)playing an important role in our life.

3）"a quantity of +名词 "与"quantities of + 名词 "作主语，谓语动词与quantity的形式一致。

A large quantity of trees has been cut down. 大量的树被砍。

【即学即练3】Huge quantities of air_______(be) being polluted.

四．自主探究

Three fourths of the earth is coverd by water.

地球的四分之三被水覆盖。

解析：名词由分数或百分数修饰时，可根据名词的类别及含义确定用单数还是复数，如果名词是可数名词复数或具有复数意义的集合名词，谓语动词用复数形式；如果名词是不可数名词，谓语动词用单数形式。

你知道以下短语修饰名词时，谓语动词用什么形式吗？请将它们分类。

Many a, a good many, the number of, a number of, a large amount of, a lot of, a great deal of, plenty of