问题补充:
The American people will never forget the 9.11 event and the psychological trauma caused to hundreds of thousands of common households.
A. that
B. it
C. which
D. what
答案:
A. that
(答案→)B. it
C. which
D. what
解析:句意:美国人永远不会忘记9.11事件和它给成百上千的家庭带来的心灵创伤。it指代9.11事件,在定语从句中做主语;which和that都做定语从句的关系词,代替先行词做主语,the psychological trauma是先行词,在从句中做宾语,可以省略。what不是定语从句的关系词。 故选B。
考点: 考查代词的用法。