题目

黄河上游与长江上游共同的特点是： (    ) A.水能资源丰富      B.含沙量大          C.有冰期            D.流量小 答案：A  ---Do you have any news about Bob? 　 ---Yeah. We ______ each other quite a lot recently. A. have been seeing   B. had been seeing     C. see       D. have seen