i have to stay at home on school nights为什么用on呢?

问题描述:

i have to stay at home on school nights为什么用on呢?

和night搭配通常用at night.
但当有定语修饰night时,其前面的介词用on.指具体或不具体的某一日或某些日.在这里school用来修饰night
其它比如说on a cold night, on Sunday nights之类的