He is a eight years old boy这句话有语法错误!
应该这样说：He is a eight- year- old boy.或者He is eight years old.
这两句话里都没有状语.
状语修饰副词?不是副词修饰副词?very quickly里,very修饰quickly.那换一种说法，百度百科上说状语可以用来修饰形容词和副词，可是又说状语修饰谓语，谓语不是动词吗？He runs very quickly.状语very quickly就是修饰谓语动词runs的，也许有一些语法书还把状语划入谓语部分呢，怎么对你说好呢？