这三个形容词是同义词,都是“愚蠢的”意思.但还是有区别的.\x0dfoolish指“无头脑的”、“缺乏常识的”、“缺乏判断能力的”.例如：\x0dIt was a foolish thing to pick a fight with his neighour.和他的邻居找碴儿打架是一件蠢事.\x0dHe is foolish to throw away such a chance.他真蠢,丢掉了这么一个机会.\x0dIt is foolish of you to say so (you are foolish to say so).你说这话真蠢.\x0dStupid指“智力差的”、“反应迟钝的”.例如：\x0dMary made a stupid mistake.玛丽犯了一个笨拙的错误.\x0dHe is very stupid in learning maths.他学数学很笨.\x0dHenry is too stupid to understand such a complicated problem.\x0d亨利太笨了,他不理解这么复杂的问题.\x0dSilly指“头脑简单瓣、不懂事的”、“傻头傻脑的”.例如：\x0dDon’t be silly!别傻!\x0dStop asking such silly questions!别再问这样傻的问题了!\x0dIt was silly of you (You were silly)to trust him.你真傻竟相信了他.\x0dSilly有时带感情色彩.例如：\x0dYou silly child.你这个傻孩子.（并无太多的贬意）\x0d概括起来,foolish相当于汉语的“愚蠢”,stupid相当于“笨”,silly相当于“傻”.\x0d另外,我们也用fool这个词.Fool是个名词,意思是“傻子”（常指先天性的智力不全者）.例如：\x0d鼓掌啊~~居然找得那么全.
