1.表示过去某一时间内(正在)进行的动作
如:I was doing my homework at 9 p.m. last Sunday.
2.表示一动作正在进行时,另一动作同时正在进行.
如:I was reading books while he was cleaning the floor.
3.表示一个动作正在进行时,另一个动作发生了
如:He played when I was studying.
4.表示过去将要发生的动作
She told us Mr.Lee was arriving here.
5.用于故事,以提供其时间背景
6.表示礼貌
[编辑本段]常用的时间状语
this morning, the whole morning, all day yesterday, from nine to ten last evening, when, while
My brother fell while he was riding his |