新概念英语第二册语法精粹及练习：过去完成进行时用法讲解及习题
一．过去完成进行时的构成为：had been + 现在分词
i had been here waiting for 30 minutes before he arrived. 他到之前，我已等了30分钟了。
二. 过去完成进行时的用法
表示动作从过去某一时间之前开始，到过去某一时间仍在进行或刚刚结束；同过去完成时一样，过去完成进行时必须以某一特定过去时间为前提。同现在完成时相似，过去完成进行时也强调动作的持续性。如：
he had been living here before he went to england.
i had been waiting in the room for half an hour before she called me in.
在她喊我进去之前，我已经在房间里等了半个小时
● she said that she had been typing a paper before i came in.
比较：
the girl had cleaned up the room, so it was tidy.
the girl had been clearing up the room, so we had to wait outside.
测试精编：
1. it ________ for four days when we arrived, so the roads were very muddy.
a. was raining b. would be raining c. had been raining d. has rained
2. he told us that he ________ there since 1982.
a. has been living b. had been living
c. would have lived d. was living
3. he had been learning english for 3 years before he came here and ________ now.
a. is still learning b. had been learning
c. was still learning d. has been learning
4. by the end of last week, he ________ in the company for 10 years.
a. had worked b. had been working
c. will have worked d. would have worked
5. not until then did people know that he ________ important military information to the enemy for a long time.
a. sold b. would sell c. had sold d. had been selling
