silly, stupid 和 foolish 都有愚蠢的意思，用的时候稍有差别。
Don't ask such a silly question. 别问这么傻的问题了。
You silly girl. 你这个傻姑娘。
He is very stupid in learning mathematics. 他在学习数学上真的很笨。
You made such a stupid mistake. 你犯了个如此愚蠢的错误。
It's foolish to fight with your boss. 和老板打架真的愚蠢。
You are so foolish to tell every thing to him. 你真傻，把什么都告诉他。
He is like a fool. 他就象个傻子一样。
Stop fooling me. 别愚弄我了。
