2009 北京 第 66 题 单选题 区分题 2009_北京卷 (英语) $66. The underlined sentence in the last paragraph probably means that ______.$ A. the problem is not approached step by stepB. the researches so far have faults in themselvesC. the problem is too difficult for researchers to detectD. research in this area is not enough to make generalized patterns 参考答案D ☆ 收藏不会,直接看解析查看原卷 →