第1个回答 2009-12-21
he was not aware of the urgence/contingcy of this issue/problem或he didn't realize.....
第2个回答 2009-12-21
he does not realize that this is an urgent problem本回答被提问者采纳
第3个回答 2009-12-21
He hasn't realized the urgency of the problem.
第4个回答 2009-12-21
He did not realized the urgency on this issue.