新概念英语第一册语法知识点总结（七）

英语自学网

　　新概念英语第一册语法知识点之过去进行时：
        　　过去完成时表示过去正在进行的动作，经常用在when, while, as引导的状语从句中。
        　　结构：was/were+doing
        　　When my husband was going into the dining room this morning, he dropped some coins on the floor.
        　　While we were having dinner, my father was watching TV.
        （兼职编辑：杨帆）