GWD-27-7

202.
            Providing initial evidence that airports are a larger source of pollution than they were once believed to be, environmentalists in Chicago report that the total amount of pollutant emitted annually by vehicles at O’Hare International Airport is twice as much as that which is being emitted annually by all motor vehicles in the Chicago metropolitan area.

A. as much as that which is being emitted annually by all

B. as much annually as is emitted by the

C. as much compared to what is annually emitted by all

D. that emitted annually by all

E. that emitted annually compared to the

请问答案为什么不能选B？？twice的用法？

B没有比较对象，as much as what？annually位置改变

twice一般都是twice as .... as

如：Interest rates are twice as high as those of our competitors.

不过也有这种用法（twice作为前限定词）：

an area twice the size of Britain

再如：Unemployment in Northern Ireland is twice the national average...

就是D的形式

1先代楼主谢谢楼上的回答~~LZ要讲究礼貌...

2AS AS似乎可以省略相同的主谓语，这里关键是丢了一个all啊改变句意