-How long did the meeting last this afternoon?- How long did the meeting last this afternoon - It was supper time ______the meeting was over.答案是when 为什么at which不行?
问题描述：
-How long did the meeting last this afternoon?
- How long did the meeting last this afternoon
- It was supper time ______the meeting was over.
答案是when 为什么at which不行?
答
当...的时候，当然用when了。
答
at which 显然是不可以的
which 表示地或物
不是时间
when才是表示时间的