hero的复数形式是什么

　　例句：

　　The hero of the novel is a ten-year old boy.

　　这部小说的主人公是个十岁的男孩。

　　He was eulogized as a hero.

　　他被赞誉为英雄。

　　A hero does something worth talking about.

　　偶像做什么值得商榷。