概念： 表示過(guò)去的過(guò)去，其構(gòu)成是had +過(guò)去分詞。　　

一、過(guò)去完成時(shí)常用的連詞有： before, by, until, when, after, once, as soon as等。例如：

He said that he had learned some English before.

By the time he was twelve, Edison had began to make a living by himself.

Tom was disappointed that most of the guests had left when he arrived at the party.

二、在什么情況下使用過(guò)去完成時(shí)？

1. 在told, said, knew, heard, thought等動(dòng)詞引導(dǎo)的賓語(yǔ)從句中，一般用過(guò)去完成時(shí)。例如：

She said (that) she had never been to Paris.

2. 狀語(yǔ)從句

在過(guò)去不同時(shí)間發(fā)生的兩個(gè)動(dòng)作中，發(fā)生在先，用過(guò)去完成時(shí)；發(fā)生在后，用一般過(guò)去時(shí)。例如：

When the police arrived, the thieves had run away.

3. 表示意向的動(dòng)詞，如hope, wish, expect, think, intend, mean, suppose等，用過(guò)去完成時(shí)表示“原本……，未能……”。例如：

We had hoped that you would come, but you didn't.

典型例題：

The students ________ busily when Miss Brown went to get a book she ____ in the office.

A. had written, left

B. were writing, has left

C. had written, had left

D. were writing, had left

答案D。 “把書(shū)忘在辦公室”發(fā)生在“去取書(shū)”這一過(guò)去的動(dòng)作之前，因此“忘了書(shū)”這一動(dòng)作發(fā)生在過(guò)去的過(guò)去，用過(guò)去完成時(shí)。句中when代表時(shí)間的一點(diǎn)，表示在“同學(xué)們正忙于……”這一背景下， when所引導(dǎo)的動(dòng)作正在發(fā)生。因此前一句應(yīng)用過(guò)去進(jìn)行時(shí)。