问题补充:
The reasonI have to go is my mother is ill in bed.
A. why...why
B. why...because
C. that...because
D. why...that
答案:
A. why...why
B. why...because
C. that...because
(答案→)D. why...that
解析:考查定语从句和表语从句:句意:我不得不走了的原因是我母亲生病在床。the reason后面跟一个定语(从句),The reason is that my mother is ill in bed. 用why引导定语从句,第二空是表语从句的连接词:原因是什么?是一个事实,这个事实用that引导,选D。