No.13 GWD1-32:
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D,我选A
实在搞不懂为什么要用would have啊!虚拟语气么?完全没必要啊 还有,they do有必要补出来么? |