过去进行时的结构：

1. 过去进行时由“主语+was/were + 现在分词”构成

如: We were having supper when the phone rang. 我们正在吃晚饭时电话响了。

2. 过去进行时的否定式由“主语+was/were not +现在分词”构成

如: This time yesterday Jack was not watching TV. He was repairing his bike. 昨天这个时候，杰克不是在看电视，而是在修理自行车。

3. 过去进行时的疑问式由“was/were +主语+ 现在分词”组成

如: Were you playing basketball at four yesterday afternoon? 你们在干什么昨天下午的时间啊 回答我啊?

时间状语：

this morning,the whole morning,all day,yesterday,from nine to ten last evening,when,while,at that time.

例句：

My brother fell while he was riding his bicycle and hurt himself;

When I got to the top of the mountain,the sun was shining。