It wasgreat shock to the world that two aero-planes crashed into World Trade Center in Ne

问题补充：

It wasgreat shock to the world that two aero-planes crashed into World Trade Center in New York o September 11th, 2001.

A. a; /

B. a; the

C. the; the

D. /; the

答案：

@@A. a; /@@(答案→)B. a; the@@C. the; the@@D. /; the

解析：shock指代具体事情时为可数名词，a great shock意为“一次沉重的打击”；由普通名词构成的建筑类专有名词需加冠词，故答案为B。