第1个回答 2011-01-28
It is not easy for us to answer this difficult question.
第2个回答 2011-01-28
This question is too hard, its too hard for us to answer本回答被网友采纳
第3个回答 2011-01-28
The question is so difficult.It's not easy for us to answer it.
第4个回答 2011-01-28
This question is so difficult that it is hard for us to answer it.
第5个回答 2011-01-28
This question is too difficult and not easy for us to answer.