过去进行时（The Past Continuous /Progressive Tense）
1. 构成
was/were+现在分词
2. 功能
ZZ1 表示过去某一时刻或某阶段内正在发生的动作
He was playing table tennis at five yesterday afternoon. 他昨天下午5点钟在打乒乓球。
The students were still singing when the teacher stepped in. 老师进来时学生们正在唱歌。
While we were watching TV, she was talking on the phone. 我们看电影时，她在打电话。
We were expecting you yesterday. 我们昨天一直在等你。（贯穿整个昨天）
We were talking about your book this morning. The book is excellent. 我们今天上午一直谈论着你的书，那本书好极了。（用来打开话题）
【提示】上下文清楚时，时间状语也可省略。例如：Oh, I was talking to myself. 噢，我刚才在自言自语呢。
ZZ2 不与时间状语连用可以表示逐渐的变化或发展
The wind was rising. 起风了。
It was getting dark. 天渐渐黑下来了。
ZZ3 用在条件或时间状语从句中表示过去将来正在进行的动作
She told me to wake him up if he was sleeping. 她告诉我如果他睡着了就叫醒他。
ZZ4 表示某种持续动作作为背景（一个画面，一种情景）,以此引出一般过去时表示的新动作
Soon the whole town was talking about it and he was plunged into remorse and shame. 不久，全城的人都对那件事议论纷纷，他陷入惶恐与羞愧之中。
The day dawned and the birds were singing. 黎明时分，鸟鸣声一片。
The baby was crying，and suddenly the crying stopped. 婴儿在啼哭，突然间哭声停止了。
The girl quickly swallowed the food she was chewing. 那女孩迅速吞下了正在咀嚼的食物。（相当于had been chewing）
Alice left the room，where she was reading a novel by Defoe. 艾丽斯离开了房间，她在那里读着雨果的一部小说。（相当于had been reading）
I was leaving the office when the telephone rang. 我正要离开办公室，电话铃响了。（含意外之意）
The rain was falling. The procession was going. Suddenly a thundering explosion was heard. 雨正下着，队伍在行进，突然听见一声巨大的爆炸声。
ZZ5 描绘一片景象
It was a summer morning in the country. The sun was just rising. A gentle wind was blowing. Some birds were singing merrily, flying from tree to tree. A young man was taking a walk on the meadow between two streams. And in the fields beyond, farmers were plowing or weeding. 这是乡间的一个夏日清晨。太阳刚刚升起。一阵微风吹过。一些鸟儿欢快地鸣唱着，在树林间飞来飞去。有一位青年，在位于两条小溪间的草地上散着步。远处的田野里，乡民们在耕地或除草。
ZZ6 表示按计划安排过去将要发生的动作，过去的预想
I thought you were leaving. 我原以为你要走的。
They were leaving for New York a few days later. 几天后他们要动身去纽约。
She was departing the next month. 她下个月离开。(＝plan to depart)
At the end of the week he phoned to say that he was returning. 他在周末打电话来说他就要回来了。
Ten of them were coming for the meeting. 他们有10个人要来参加会议。
He knew that the plane was taking off in ten minutes. 他知道10分钟后飞机就要起飞了。
Her parents were intending her to be a teacher, but she made up her mind to be a painter. 她父母原先想让她当教师，可是她下定决心要当画家。
ZZ7 与forever，continually，always，constantly等连用，表示某种感情色彩
She was always changing her mind. 她老是改变主意。（不满）
My mother was constantly praising her. 我母亲总是表扬她。
She was forever grumbling. 她老是发牢骚。
She was always making mistakes. 她老是出错。
He was always thinking of others. 他总是为别人着想。
【提示】下面的句子也表示某种感情色彩：
He was fighting with the whole world. 他在同整个世界作对呢。
What a happy time they were spending! 他们过得多么快活啊！
ZZ8 表示婉转语气，用以提出请求，只限于want，hope，wonder等动词
I was wondering if you could help me. 不知你能否帮个忙。
I was hoping you could send me the book. 我一直希望你能把那本书寄给我。
I was wondering if you'd look after my dog while I'm away? 我想知道我不在时你能不能帮我照看一下狗？
ZZ9 表示动作的未完成性
过去进行时可以表示动作的未完成性，即对某事了解得不全面，希望得到更详细的情况。例如：
A：Another expressway will be built between Shanghai and Nanjing. 上海和南京之间将另建一条高速公路。
B: Yes, I was reading about it in the newspaper. 是的，我在报纸上才看到。
A: Did you hear about the new space program? 你听说过那个新的太空计划了吗？
B: Yes, Professor Li was telling me the other day. 是的，李教授前天还跟我谈到过。
A: Do you know he's been arrested? 你知道他被捕了吗？
B: Yes, Mark was telling me about it in the morning. 是的，马克今天上午还跟我说起这事。
ZZ10 表示继续刚刚中断的谈话，用于日常生活中
As I was saying, we'd better leave things as they are until the police arrive. 正如我刚才说的，在警察到来之前，我们最好保持现场原样。
As I was telling you, the boy took his stubbornness from his father. 正像我刚才告诉你的，这男孩的犟脾气是他爸爸传给他的。
As I was saying, bus services should meet the needs of suburbs. 正如我刚才说的，公共汽车服务应适应郊区的需要。
As I was telling, money is a wonderful thing, but it is possible to pay too high a price for it. 正如我刚才对你所说的，钱固然是好东西，但是为了钱而付出的代价往往太高了。
As he was telling me, we must depend upon ourselves to make our own way as best we can. 正如他所告诉我的，我们必须依靠自己竭尽全力走自己的路。
ZZ11 表示最近过去的事情（为一种说话口气比较随便的用法）
I was hearing Frank had entered the college. 我刚听说弗兰克上大学了。
I was asking what you thought of it. 我在问你的想法。
Jane was telling me about it this morning. 简今天上午告诉我那件事的。
ZZ12 表示将来的猜想情况，有时表示不耐烦等情绪
I thought you were never coming. 我以为你总不会来了。
I'd rather you were going at once. 我宁愿你立即走。
If the students were leaving tonight，I'd like to go with them. 如果学生们今晚就走，我想同他们一起走。
【提示】过去进行时的时间关系也可由上下文或具体情景表示。例如：It was raining hard，but no one stopped working. 雨下得很大，但没有人停止工作。
ZZ13 表示过去未实现的愿望或打算
She was coming. 她本来要来的。
I was seeing her tomorrow. 我本来打算明天会见她。
He was watching the play yesterday，but he was too busy. 他昨天本来要看那场戏的，可是太忙了。
I was going to phone you, but I just didn't have time. 我本想给你打电话的，但就是没有时间。
The basketball match was taking place the next day, but it had to be cancelled because of the heavy rain. 篮球赛原定第二天举行的，但因大雨只得取消。
ZZ14 表示对比
He was not sitting idle, he was making preparations. 他没有闲坐着，他在做准备。
While the children were playing in the shade, their parents were working in the scorching sun. 孩子们在树荫下玩耍，而他们的父母却在烈日下劳作。
ZZ15 表示原因
I didn't hear what you said; I was looking at the picture. 我没有听见你的话，我在看那幅画。
I haven't finished my homework yet, I was helping my mother in the kitchen all day yesterday. 我还没完成作业，我昨天一整天都在帮妈妈干厨房活。
ZZ16 对所说的话进行强调
在小说的对话中，有时引述动词不用一般过去时，而用过去进行时，意在强调所说的话，语气较重，且更为生动。例如：
A：“Did they catch her?” Mary was asking. “他们抓住她了吗？”只听得玛丽问道。
B：“No，she escaped.” Tom told her. “没有，她逃走了。”汤姆告诉她。
A：Do the students enjoy reading the novel? 学生们喜欢读这部小说吗？
B：“Some of them do，” she was saying. “But others don't.” “有些人喜欢，”她说道，“但是别的人不喜欢。”
ZZ17 过去进行时和一般过去时的用法比较
（1）过去进行时可以表示过去反复做的动作，而一般过去时表示只做一次的动作。例如：
She was waving her hand. 她不断地挥手。
She waved her hand. 她挥了挥手。
The frog was jumping up and down. 青蛙不断地跳着。
The frog jumped up and down. 青蛙跳了一下。
She was nodding. 她不停地点头。
She nodded. 她点了点头。
（2）leave，arrive，start，begin，die等的过去进行时表示“刚刚开始，快要完成，即将……”，而一般过去时表示“已经……”。例如：
I was starting to write a letter when the phone rang. 我刚开始写信，电话铃就响了。
The effect of the drinks was beginning to fade. 酒意正在开始消失。
But to Annie, it was beginning to seem the opposite. 但是安妮已经开始觉得事情恰恰相反了。
The train was stopping. 火车快要停了。
The train stopped. 火车停了。
She was dying. 她快要死了。
She died. 她死了。
He was leaving. 他快要离开了。
He left. 他离开了。
（3）过去进行时表示正在进行尚未完成的动作，而一般过去时则表示已完成的动作。例如：
They were talking about it. I didn't want to disturb them. 他们在谈那件事，我不想打扰他们。
They talked about it and made a decision. 他们谈了那件事，做出了决定。
She was making preparations for the journey then. 她当时在为旅行做准备。
She made all the preparations for the journey in one day. 她花了一天时间就为旅行做好了准备。
She was writing a letter at nine last night. 她昨晚9点钟在写信。
She wrote a letter and posted it. 她写好了信就寄走了。
（4）过去进行时同forever, always, frequently等连用，略带感情色彩，而一般过去时则表示客观陈述。例如：
She was forever complaining about her job. 她老是对她的工作提出抱怨。（厌烦）
She complained about the weather. 她抱怨天气。（客观表述）
He's always leaving his clothes on the floor!他老把衣服扔在地上！（责备）
He left his clothes on the floor. 他把衣服放在地上。（客观表述）
His sister is always helping others. 他妹妹总是帮助别人。（赞扬）
His sister helped the old man up the stairs. 他妹妹帮那位老人上楼。（客观表述）
（5）work, feel, wait, rain, snow, wear, cough等动词，不表示动作完成，有时用一般过去时和过去进行时均可，意思上没有什么差别。例如：
He was working all day yesterday. 他昨天整整干了一天。
He worked all day yesterday.
It was snowing the whole night. 下了一夜的雪。
It snowed the whole night.
She was waiting from morning till night. 她从早一直等到晚。
She waited from morning till night.
She was wearing the overcoat the whole day. 她整天都穿着那件大衣。
She wore the overcoat the whole day.
I wasn't feeling well that night. 那天夜里我感到不舒服。
I didn't feel well that night.