wasdo还是wasdoing

问题描述

精选答案

看情况， 如果是过去正在做什么 ，就用过去进行时 was doing sth ,如He was watching Tv when i came in.但是be to do 是be 动词+ 不定式。

表示将来，命令。命运等， 如 he is to present the awards at the meeting tomorrow.