一个八岁的男孩用英语怎么说an eight-year-old boy这种说法我知道对,那么an eight years old boy这种说法对吗?

对啊 0 0
一个意思

eight-year-old 是形容词，可以放在boy前面。
如果你说The boy is eight-year-old. 是正确的，The boy is eight years old. 也是正确的。

a boy at his eight

都对

不可以用an eight years old boy,因为eight year old 是形容词,不能用plural form.
He is eight years old 这个用法才正确.

一个八岁的男孩：
an eight-year-old boy
a boy of eight (years old)