If the cap fits
【英文解释】If sb's words are right, then accept them.
【短语来源】If the cap fits, wear it has been around since at least the early 18th century, and is probably older. A work of 1600 called Pasuil's fools-cap with the passage 'where you find a head fit for this Cappe, either bestowe it upon him in charity,or send him where he may have them for his money's suggests that the expression was known then, and also reminds us that the cap to be worn is a dunce's cap. In America, this saying is more likely to be found in the form 'If the shoes fits...' or even, perhaps under the influence of Cinderella story, 'If the slipper fits...'
probably adv. 大概, 或许, 很可能
in charity 出于恻隐之心
for one's money 依照本人的意见 比如说for my money 依我看，我觉得
If the cap fits, wear it.这句俗语大约出现在18世纪早期，甚至更早。1600年的一部名为《Pasuil's fools-cap》的文学作品中就有这么一句'where you find a head fit for this Cappe, either bestowe it upon him in charity,or send him where he may have them for his money（字面直译是“如果你找到适合这顶帽子的人，或是出于怜悯，将帽子授予此人，或是按照此人的意见将帽子寄到他能收到的地方。”）这表明该短语在那时就已为人们熟知。
在美国，这一段与更多地被表达为If the shoes fits...，或是受灰姑娘故事的影响，说成If the slipper fits...。因为灰姑娘童话的英文版本里面就有这样的表达。
比如说你作业没做好，老师觉得你每天玩游戏花了太多的时间，影响了学习。你不服气，我跟你是一个宿舍的，我很清楚老师说的是对的，于是我可以说If the cap fits。
【有例有句】-He said I eat too many candies, I don't think so.
-If the cap fits.