To develop more accurate population forecasts, demographers have to know a great deal more than now about the social and economic determinants of fertility.
have to know a great deal more than now about the social and economic have to know a great deal more than they do now about the social and economical would have to know a great deal more than they do now about the social and economical would have to know a great deal more than they do now about the social and economic would have to know a great deal more than now about the social and economical
答案是E,但我不明白C错在哪里?尽量补出谓语动词或助动词不是比E更好吗?
欢迎光临 国际顶尖MBA申请交流平台--TOPWAY MBA (http://forum.topway.org/forum/) | Powered by Discuz! 7.2 |