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1.構成: had been doing

2.用法:

①.表示過去某時間或動作以前己經(jīng)完成的動作或己存在的狀態(tài), 即“過去的過去”

　　　 　a. When all his money had gone, Marx had to leave his house in London.

　　　 　b. Marx had learned some English before he got to England.

　　　 　c. He said he had never been to Shanghai.

　　　 　d. By the middle of last month I had lived in Beijing for five years.

②.在帶有after / before引導的時間狀語的句子中, 由于after / before本身的詞義己經(jīng)表明了時間的先后, 所以這類句子中常用一般過去時代替過去完成時

　　　 　a. We left the house before it began to rain.

　　　 　b. I didn’t wait long before he came.

　　　 　c. After we finished the tea, we all sat on the grass.

　　　 　d. After he arrived in England, Marx worked hard to improve his English.

1.構成: had done

2.用法:

①.表示過去某一時刻正在進行或一段時間內(nèi)一直在進行的動作或情況

　　　　 a. This time yesterday we were having an important meeting.

　 　　　b. A year ago we were living in Shanghai.

　 �、�.過去進行時常與always, continually, frequently等詞連用, 表示過去經(jīng)常發(fā)生或反復發(fā)生的情況

　　　　 a. The old man was always losing his way.

　　　　 b. The two brothers were frequently quarrelling.

③.表示過去將要發(fā)生的動作, 這一用法僅限于一些表示位置轉(zhuǎn)移的動詞, 如: go, come, start, stay, leave等

④.過去進行時經(jīng)常與一般過去時配合使用, 過去進行時表示過去的時間背景

　　　　 a. The teacher was giving us a lesson when Tom walked into the room.

1.構成: was / were doing

2.用法:

①.表示過去某一時刻或某一段時間內(nèi)發(fā)生的動作或情況, 其中包括習慣性動作

　　　　 a. I met him yesterday.

　　　　 b. I used to go to school early every morning.

　　　　 c. He entered the classroom, sat down at his desk and began to work.

　　　　 d. Last night, I listened to the radio for two hours and went to bed at midnight.

②.在時間, 條件狀語從句中用一般過去時代替過去將來時

　　　　 a. Helen had left her keys in the office so she had to wait until her husband came home.

　　 ③.用一般過去時的句子一般有過去的時間狀語, 有時也用地點狀語暗示動作的發(fā)生是在過去

　　　　 a. Have you seen a pen ? I left it here this morning.

1.構成: 用動詞的過去式表示

4.現(xiàn)在完成時與現(xiàn)在完成進行時的區(qū)別: 前者著重表示過去動作對現(xiàn)在的影響或結(jié)果; 后者著重表示過去動作的持續(xù)進行

　　　　 a. I have written six letters since I got back.我己經(jīng)寫了六封信 (強調(diào)結(jié)果)

　　　　 b. I have been writing letter since I got back. 我回家后一直在寫信 (強調(diào)“一直在寫”)

　　　　 c. I have read this book.我讀過這本書了(強調(diào)“讀過”這一結(jié)果)

　 　　　　d. I have been reading this book.我一直在讀這本書 (強調(diào)“一直在讀”)

3.用法:

①.表示現(xiàn)在之前的一段時間里一直進行的動作, 此動可能仍在進行, 也可能剛剛停止

　　　　 a. I have been reading the book all the morning.

　　　　 b. He has been staying here for two hours.

　　　　 c. I have been living in Beijing since 1972.

②.表示現(xiàn)在之前的一段時間里一再重復的動作

　　　　 a. I have been calling you several times in the past two days.

2.特征: 現(xiàn)在完成進行時兼有現(xiàn)在完成時和現(xiàn)在進行時兩者的特點

①.它具有現(xiàn)在完成時的特點, 即表示動作發(fā)生在過去, 延續(xù)到現(xiàn)在或?qū)ΜF(xiàn)在產(chǎn)生影響

②.它具有現(xiàn)在進行時的特點, 即可以表示此動作仍在進行或還會繼續(xù)

　　　 　a. Mr. Smith has taught English for twenty years. ( 至今為止教過二十年英語, 至于teach是否結(jié)束或是否延續(xù), 不得而知)

　　　 　b. Mr. Smith has been teaching English for twenty years.( 現(xiàn)在仍在教英語,而且將持續(xù)下去)