去完成进行时与过去完成时的用法

你说的的是 had been doing 和 had done 结构吗?
过去完成进行时(had been doing )表示过去某一时刻之前开始的动作或状态一直延续到过去某一时刻.例如：
It had been raining cats and dogs for over a week and the downpour had caused landslides in many places.
过去完成时(had done)表示过去某时间前已经发生的动作或情况,这个过去的时间可以用by,before等介词短语或一个时间状语从句来表示；或者表示一个动作在另一个过去动作之前已经完成.
1)We had just had our breakfast when Tom came in.
2)By the end of last year they had turned out 5, 000 bicycles.
至于哪个延续时间长?只有前者表动作的持续,后者表动作的完成.