Sleep on it

　　Tom: I really don’t know what to do.
　　Ann: Sleep on it. Maybe you will have a good idea tomorrow.
　　都说今日事今日毕，但有些事还是不得不等到明天。sleep on it就是要带着某件事先睡一觉，意思是“明天再说；考虑一晚再说”。