问题补充:
The reason he was late for school was he had to send his mother to a hospital.
A. that; why
B. why; because
C. why; that
D. that; because
答案:
A. that; why
B. why; because
(答案→)C. why; that
D. that; because
解析:句意:他为什么会上学迟到的原因是他不得不送妈妈去医院。第一空填why。引导定语从句,先行词是reason,定语从句中缺少原因状语,第二空填that,连接表语从句,当主语是the reason的时候,表语从句用that连接,所以选C。