we were watching an exciting sports program on TV__the lights went out.we were watching an exciting sports program on TV___the lights went out.A.as B.when C.so D.while原因.
来源：学生作业帮助网 编辑：六六作业网 时间：2024/05/07 04:07:17
we were watching an exciting sports program on TV__the lights went out.we were watching an exciting sports program on TV___the lights went out.A.as B.when C.so D.while原因.
we were watching an exciting sports program on TV__the lights went out.
we were watching an exciting sports program on TV___the lights went out.
A.as B.when C.so D.while
原因.
we were watching an exciting sports program on TV__the lights went out.we were watching an exciting sports program on TV___the lights went out.A.as B.when C.so D.while原因.
选B：原因如下
1、若主句表示的是一个短暂性的动作,而从句表示的是一个持续性动作时,两者都可用.如：
He fell asleep when [while] he was
reading.他看书时睡着了.
I met him when [while] I was taking a walk in the park.
我在公园散步时遇到了他.
2、若主、从句表示两个同时进行的持续性动作,且强调主句表示的动作延续到从句所指的整个时间,通常要用
while.如：
Don’t talk while you’re eating.吃饭时不要说话.
I kept silent while he
was writing.在他写的时候,我默不作声.
3、若从句是一个短暂性动作,而主句是一个持续性动作,可以 when 但不用
while.如：
When he came in,I was listening to the radio.他进来时,我在听收音机.
It
was raining hard when we arrived.我们到达时正下着大雨.
4、若主、从句表示的是两个同时(或几乎同时)发生的短暂性动作,一般要用 when.如：
I thought of it just when
you opened your mouth.
就在你要说的时候,我也想到了.