[求助]大全764

1.        The gyrfalcon, an Arctic bird of prey, has survived a close brush with extinction; its numbers are now five times greater than when the use of DDT was sharply restricted in the early 1970’s.

(A) extinction; its numbers are now five times greater than

(B) extinction; its numbers are now five times more than

(C) extinction, their numbers now fivefold what they were

(D) extinction, now with fivefold the numbers they had（A）

(E) extinction, now with numbers five times greater than

我搜索看到有人问过这里number和numbers的问题，但我对为什么选A不明白，A是个什么比较结构呀，我觉得比较的前面是numbers，后面怎么又是个when....,比较结构真是烦死人。

now和when不同时间点的its numbers比较. its numbers were省略.

一针见血，我懂了，谢谢！是不是主谓都相同的时候就可以省略，这里前面的谓语和后面的谓语时态不一样，也可以省略吗？

我感觉系表结构中可以。