GWD, Questions about the use of "than"

Soaring television costs accounted for more than half the spending in the presidential campaign of 1992, a greater proportion than it was in any previous election.

1. a greater proportion than it was
2. a greater proportion than

3. a greater proportion than they have been
4. which is greater than was so
5. which is greater than it has been

   Answer: B, not A

why is the answer is D, not E?

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.

1. have to know a great deal more than now about the social and economic
2. have to know a great deal more than they do now about the social and economical
3. would have to know a great deal more than they do now about the social and economical
4. would have to know a great deal more than they do now about the social and economic

5. would have to know a great deal more than now about the social and economic

   Answer: D, not E

up,

Thanks for your help!

16、it理论上应该指代Soaring television costs, 但是costs是复数, 应该用they

B选项其实是a greater proportion than （they were）in any previous election.  把they were省略了

32、they would have to do。。。than they do now 。。。

。。。than。。。必须要同等才能比较

 do要和 do 比较