1.概念：表示某个正在进行的动作或状态，持续到过去某个时刻，还未完成，一直持续到之后的当前才结束。

2.基本结构：主语+ had + been + doing +其它

3.例子：

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?

4.特殊含义：

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)