when引导的句子可用瞬间和持续性动词
while引导的句子动词一般是持续性动词
My mother was cleaning the floor while(when)my father was tidying up the shelf.
When(不能用while)he came in,we are talking loudly.
when引导的句子可用瞬间和持续性动词
while引导的句子动词一般是持续性动词
My mother was cleaning the floor while(when)my father was tidying up the shelf.
When(不能用while)he came in,we are talking loudly.