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
为什么要would have to(D)？我选的是 B 作者: frankzhiwei 时间: 2010-9-21 14:32
求解答呀~作者: jbc88 时间: 2010-9-21 15:18
economical不对，这是经济的，节约的。
1. economic vs economical "economic" means "having to do with "economics and/or the economy" (this is the intended meaning). "economical" means "efficient" or "at low cost/expense". (this is not the intended meaning.)
2. more than now vs. more than they do now In A and E, you are not comparing similar things. Literally you're comparing the knowledge about social and economic determinants to now. Consider the following example: I have to run faster than now. This is incorrect. what is now? This doesn't make any sense. I have to run faster than I do now. Correct
3. would have to vs have to There's a slight rhetorical difference ("would have to" carries the connotation that these forecasts are just hypothetical and don't actually have to be developed, or that at least it's not important, while "have to" implies that these forecasts are important and have to be made).作者: frankzhiwei 时间: 2010-9-25 00:46
哥！牛B~谢谢！