2.基本结构：主语+have/has +been +doing+其它
4.例子：I have been sitting here for an hour.我已经在这里坐了一个小时。
The children have been watching TV since six o'clock.从6点起，孩子们一直看电视。
2.基本结构：主语+ had + been + doing +其它
She had been suffering from a bad cold when she took the exam.她在考试之前一直患重感冒。
Had they been expecting the news for some time?他们期待这个消息有一段时间了吧?
①尚未完成：He had been writing the novel.他已经在写小说了。(他没写完)
②企图：He had been studying the meaning of this proverb.他曾经学习过这个谚语。(他曾努力学习过它)
③未得结果：We had been studying what our enemy had said.我们一直致力于敌人所说的。(但是我们没有理解)
④最近情况：He had been quarrelling with his wife.他和他的妻子吵了一场架。(最近)
⑤反复动作：He had been asking me the same question.他一直问我相同的问题。(屡次)
⑥情绪：What had he been doing?他做了什么?(不耐烦)
2.基本结构：shall/will have been doing
I shall have been working here in this factory for twenty years by the end of the year.
If we don't hurry up the store will have been closing before we get there.
2.基本结构：should/would + have + been +现在分词
3.例子：He told me that by the end of the year he would have been living there for thirty years.