1.过去完成式的形式是had+过去分词。
2.过去完成式表示过去某一时间或某一动作之前已经完成的动作或存在的状态,这一过去的时间可由by,before引导的时间副词片语或子句或从上下文中表示出来。
So I had finished ironed your shirt before you got up.
所以我在你起床前就熨好了你的衬衫。
I had finished typing before lunch.
我在午饭前已打完字。
3.过去完成式表示过去某一时间以前开始一直延续到那个时间并可能继续下去的动作或状态,常和by或since引导的表示时间的片语或子句连用。
You had done housework for 2 months when I heard your complaints.
到我听到你的抱怨时止，你已经做了两个月家务了。
He had studied English for five years when he took the exam.
到考试时止,他已经学了五年英语。
4.过去完成式可表示过去未实现的希望或计划。
I had hoped that you became an industrious man.
我曾希望你成为一个勤劳的男人。
I had hoped to pass examination.
我曾希望能通过考试。
5.过去完成式表示在过去某时或某个动作之前发生的动作、存在的状态或表示经历、经验。
I said I had been angry for your laziness since we married
我说自从我们结婚以来我一直为你的懒惰生气。
He said that he had been very busy since we last met.
他说自从我们上次会面以来他一直很忙。