学员HQ9EDU09060: 老师,请问When,while,as,前后应该加的时态是什么?
老师回复:when, while,as的区别并不在时态上,时态的确定要根据句子中的时间状语.
这三个连词中,when 用得最广,常可代替while 与as.与while比较,when 所引导的从句,动词既可是延续性的,也可是终止性的。as在这一点上与when 相同,while所引导的从句中,动词只能是延续性的。例如:
The telephone rang when(while) I was taking a bath.
All the students were sleeping soundly when the fire broke out. (此句中不可以用while)
两个延续性动作同时发生又具有对比意味时,用while,在这样的复合句中,主从句的时态通常上相同的。例如:
Father was preparing a report while I was playing games.
While I played the violin, my sister did her homework.