several可以单独作主语，也可以用“several  of + 复数名词”作主语，它们后面的谓语动词都应该用复数。例如：
Of the eggs, several were broken. 这些鸡蛋有几个是破的。（《张道真高级英语词典》p.1394）
Several of us are going to the film. 我们有几个人要去看这部电影。（《张道真高级英语词典》p.1394）
Several of them are ill. 他们有几个人生病了。（《张道真高级英语词典》p.1394）
There are several here that I don't know. （张道真主编《现代英语用法词典》修订版 p.1359）
Several of us decided to work home. （张道真主编《现代英语用法词典》修订版 p.1359）
Several (of them) were broken. （张道真主编《现代英语用法词典》修订版 p.1359）
Several of  the apples are bad, and several more have worm holes. （张道真主编《现代英语用法词典》修订版 p.1359）
Several of the children were in the garden. （张道真主编《现代英语用法词典》修订版 p.1359）