题目

下列因素不能直接导致海陆变迁的是                                        (      )  A．地壳的变动       B．海平面的升降        C．人类活动       D．寒潮天气 答案：DIf it were not for the fact that I ________ very busy, I would go with you. A. am           B. was              C. were         D. should be