如果你 “put your thinking cap on（戴上你的思考帽子）”，那么你就在 “认真思考某件事情”。在遇到一个需要通过深思熟虑去解决的难题时，就可以使用这个表达。

例句
This exam will be difficult. However, if you put your thinking cap on, you'll be fine.
这场考试会很难。不过，只要你认真思考作答，就没问题。

I didn't know how to work out the math problem at first, but I put my thinking cap on and found the answer.
我起初不知道该怎样解答这道数学题，但在仔细思考之后，我找到了答案。

We'll need to put our thinking caps on to solve this riddle.
我们需要开动脑筋，才能解开这个谜语。