GWD1-Q32 问题

若潺

GWD1-Q32:

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 economical


key：D
想问一下为什么不能用状语比较？就是直接用now 和以前的比较 就是A选项

九珍豆腐

than now about  
所以have to 表示现在和现在比   句子意思应该是将来和现在比 所以要加would