Question

I was doing my homework（ ）my mother was doin

I was doing my homework（ ）my mother was doing some sewing.A.during B.when C.while D.after

Answer 1

1. 这里应该用while

 when表示某个点时间发生的，如 ：I was doing homework when mum came back.
 while表示两个事情同时进行中，强调的是时间段，而且接的大多数都是进行时态，如：I was    singing while he was dancing。