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 thesocial 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
The answer is "D".
我知道這邊的重點在"economical & economic";不過為什麼可以使用would???
原題中並沒有使用而且我也不覺得句意上需要
可以請問一下各位嗎???