过去进行时.doc

文档介绍：过去进行时
过去进行时表示过去某一点时间正在进行的动作或者过去某一段时间内一直进行的动作。
1. 构成
was /were + doing，例如：
I was watching TV at 9 o’clock last night.
at 9 o’clock last night是时间点
They were playing football all afternoon.
all afternoon是时间段
2. 过去进行时的标志词
at 8 o’clock last night, this time yesterday等。例如：
I was having lunch at home this time yesterday.
昨天的这个时候我正在吃午饭。
At that time she was writing a book.
那阵子她在写一本书。（表示她在那段时间里一直在做那件事情。）