过去进行时

过去进行时
Past Progressive tense 过去进行时
Conception概念：过去进行时（Past continuous tense或Past Progressive tense）表示在过去某一时刻或某一段时间内发生或进行的动作或状态。

结构Structure ：Be动词的过去式（was/ were）+ doing
使用情景Situation
1.表示过去某时正在进行的动作
过去进行时这一用法，通常也要把时间状语表示出来，或者通过上下文把时间关系暗示出来。

这种时间状语可以表示过去某一时刻正在进行的动作。

What were you doing yesterday at 7 p.m. ?
When I went downstairs, they were already eating breakfast.
From 1983 to 1988, he was teaching at Yale.
2.表示过去某种习惯性动作
过去进行时所表示的习惯动作通常是指过去某一阶段暂时性的习惯。

George was getting up at 5 every day that week.
过去进行时也可与always, constantly, continually等状语连用表示感情色彩。

My brother was always losing his keys.
Alice was constantly changing her clothes.
3. 表示过去将来时间里的动作
过去进行时在一定上下文中也可表示按照计划安排即将发生的过去将来事态。

?They were leaving a few days later.
The summer vacation was drawing near, but nobody knew where they were going for the holiday.
4.表示现在时间和将来时间里的动作
过去进行时的这种用法是为了表示婉转口气
用过去进行时表示婉转口气只限于hope, want, wonder等动词，主要表示有礼貌的请求
I was wondering if you’d like to come out with me one evening.
I was hoping you could send me some books.
过去进行时与一般过去时用法比较
1.表示已完成的动作用一般过去时，表示未完成的动作用过过去进行时
I was reading a novel yesterday.
I read a novel yesterday.
They were building a dam last year.
They built a dam last year.
2.一般过去时通常只说明过去某时发生某事，而过去进行时则侧重在动作的持续时间，而不仅是说明事实
It rained/ was raining all night.
He worked/ was working all through the night.
3.当一般过去时与过去进行时同时出现在句中时，通常是表示较短的动作用一般过
去时，表示较长的动作用过去进行时
While I was writing a letter, my wife came in.
I broke a glass while I was cooking the dinner.
I was running downstairs when I slipped and fell.
The pupils were talking noisily when the teacher stepped in.
A thirsty ant was climbing down a blade of(一片) grass that grew beside a spring（小溪）. She was trying to reach the water so she could take a drink. Unluckily she slipped（滑倒）and fell into the spring.
Now a dove（鸽子）was sitting on a branch over the water. She saw the ant fall in and was filled with pity（惋惜）. Quick as a wink（眨眼）she pulled off a leaf and let it fall into the spring.
The little raft（小船）settled down（落到）on the water right beside the drowning（溺水的）ant. The ant climbed down on the leaf and was soon safe on shore（岸）again.
But what did she see? Hidden behind a bush（灌木）, a hunter was spreading（铺开，展开）his net. He was going to catch the dove. “No!” the grat eful（感激的）ant said. “You shall not take the bird that saved my life!” And with all her might （力气）she bit the hunter on his bare（裸露的）foot. With a cry the hunter dropped his net, and the dove flew away to the wood. One good turn deserves（赢得）another.。