问题补充:
The reason he explained for his being late was his alarm clock didn’t work.
A. why; because
B. that; because
C. /; that
D. for which; that
答案:
A. why; because
B. that; because
(答案→)C. /; that
D. for which; that
解析:第一空为定语从句先行词是The reason关系词要在从句中做explained的宾语所以要用关系代词which\that还可省略;第二空考查表语从句不缺成分用连接词that,所以答案为C