过去进行时

1. 过去进行时的形式:
was/were + 现在分词

2. 过去进行时的用法:
1) 表示过去某一时刻正在进行的动作
* We were expecting you yesterday. 我们昨天一直在等你。
* What book were you reading when I saw you at four yesterday afternoon? 昨天下午四点我看见你时，你在看什么书？
* I wasn't having a talk with Li Hua at that time. 那时我没在跟李华谈话。
* Was he watching TV when you came back?　你回来的时候，他正在看电视吗？
* Kate was reviewing her lessons at eight last night. 昨晚8点的时候凯特正在复习功课。
* While my mother was watching TV, I was making a kite. 我妈妈在看电视的时候，我在制作风筝。

2) 描绘一幅景象或故事背景
* Last Sunday, I went and sat on the river bank as usual. Some children were playing games on the bank and there were some people rowing on the river. 上星期天，我和往常一样，又去河边坐着。河岸上有些孩子正在玩耍，河面上有些人正在划船。
* It was snowing as the medical team made its way to the front. 那支医疗小组往前线行进时，天正下着雪。

3) 表示按计划、安排过去某时将要发生的动作
* A train was leaving at midnight for Beijing. 半夜有一趟列车开往北京。
* They said that they were going back to their own country. 他们说他们将回自已的国家。

4) 与always, constantly, continually, forever 等连用，表示感情色彩
* She was constantly complaining of the cold. 她总抱怨天气太冷。
* He was always making noises. 他总爱大声喧闹。
* He was always thinking of his work. 他总是一心想着他的工作。
* She was forever complaining. 她老是抱怨。