谓语动词构成：I/we/you/they had worked; he/she/it had worked

(1) 表示过去某一时刻之前已经完成的动作，常与由by，before引导的时间状语连用

We had learned 5000 words by the end of last month.

到上个月底为止我已经学了五千个单词.

I had finished the composition before supper. 晚饭前我就已经把作文写完了.

(2) 表示过去某一动作之前已经完成的动作，常与由when，before等连词引导的时间状语从句连用

When I woke up it had already stopped raining. 我醒来的时候雨就已经停了.

I hadn’t learned any English before I came here. 我来这儿之前没学过英语.

(3) 用于宾语从句或间接引语中

I wondered who had taken the umbrella without permission.

我想知道谁不经允许就把雨伞拿去.

He told me that he had passed the exam. 他告诉我他已通过考试.

(4) 某些动词的过去完成时表示一个打算要做却没有做成的事.

I had intended to come over to see you last night, but someone called and I couldn’t get away. 昨晚我本打算来看你，但有人来找，脱不开身.

We had hoped to catch the early bus, but found it was gone.

我们本来希望乘早班车，却发现车已开了.

(5) 用于表示与过去事实相反的虚拟条件从句中

If you had come yesterday, you would have met him.

如果你昨天来的话，你就已经见到他的面了.

She would have come if she hadn’t been so busy.

要不是这么忙的话，她就已经来了.