标题: 求助 og12 第41题 为什么要用would 啊？？ [打印本页] 作者: cloudyay 时间: 2012-7-23 16:53 标题: 求助 og12 第41题 为什么要用would 啊？？ To develop more accurate population forecasts, demographers have to know a great deal more than now about the social and economic determinants of fertility. (A) have to know a great deal more than now about the social and economic (B) have to know a great deal more than they do now about the social and economical (C) would have to know a great deal more than they do now about the social and economical (D) would have to know a great deal more than they do now about the social and economic (E) would have to know a great deal more than now about the social and economic