The day when (=on which) she arrived was Thursday.为什么when可以用on which替换?我的意思是为什么是on which而不是其他比如at which ,in which等,请问which前面加什么词是怎么判断的?

问题描述:

The day when (=on which) she arrived was Thursday.为什么when可以用on which替换?我的意思是为什么是on which而不是其他比如at which ,in which等,请问which前面加什么词是怎么判断的?