If the cap fits,wear it.

　　Definition: if the statement about someone is true, then one must accept it.

　　【世博精解】

　　这个习惯用语中的cap也可以是shoe或者hat,一般来说，If the hat/shoe fits，wear it主要是美语。而且，这个惯用语可以直接简单地说成If the cap/hat/shoe fits.它的意思是如果所说的话符合你的情况，你就应该接受或者承认。这里的statement通常是不太令人愉快的,如：意见、批评或惩罚等。如果某个人因所作的事感到愧疚却又不肯承认或接受，你就可以用这句短语了：Look, I didn’t say who was to blame for this mess, but if the cap fits, wear it.又如校长开会时绝对可能严肃地说：I have noticed that there are some classroomsswheresthe pupils have been in at least five minutes before their teacher appears. I will name no names but, if the cap fits, wear it.

　　Example dialog:

　　Mum: Tell mummy who broke the vase in the corner, good boys.

　　好孩子，告诉妈妈谁把角落的花瓶摔破了？

　　Tom: I don’t know. Not me, mum.

　　我不知道，不是我，妈妈。

　　Joe: You big liar. If the cap fits, wear it.

　　你这个大话王。是你就承认呗。