[10-20 18:04:55] 来源：http://www.67xuexi.com 教育学习 阅读：85632次
过去完成进行时(past perfect continuous tensewww.67xuexi.com/
1)过去完成进行时的形式一律为had been + 现在分词，无人称和数的区别。
2)过去完成进行时的用法 过去完成进行时表示动作在过去某一时间之前开始并延续到过去这个时间，这一动作可能还在进行，也可能已经停止。如：
He told me that he had been waiting for me for two hours.他对我说他等了我两小时。(动作不再延续)
The baby had been crying for fifteen minutes when her mother came in.妈妈进来时，婴儿一直哭了十五分钟。(动作可能还在进行)
It seemed to her that the boys had been shouting for a long time.她似乎觉得这些男孩一直叫喊了很久。(动作可能还在进行)
The teacher had been teaching for forty years by the time he retired，这位教师退休前一直教了四十年的书。(动作不再进行)