“It is difficult to answer that question” means _______ .

题目

“It is difficult to answer that question” means _______ .
A. that question is not difficult to answer
B. that question is difficult to answer it
C. it is difficultly to answer that question
D. it is hard to answer that question
B为什么不可以

答案

B的语法不对,that question is difficult to answer就是个完整的句子,而B中的it 就是指that question,句子开头就已经说了,很重复,而且that question is difficult to answer ,开头用it做为形式主语,所以才有了D的it ...