OG11黄皮书-18题：关于be动词的省略。请教：）

doudoucc

18.
Computers are becoming faster, more powerful, and more reliable, and so too are modems, they are the devices to allow two or more computers to share information over regular telephone lines.

(A)
so too are modems, they are the devices to allow

(B)
so too are modems, the devices that allow

(C)
so too modems, the devices allowing

(D)
also modems, they are the devices that allow

(E)
also modems, which are the devices to allow

请问在B、C选项中，为什么C就不对呢？这里的are为什么不可以省略啊。谢谢。

doudoucc

heihei，我觉得你说得有点道理。可是还不明白的是，这里so too是个什么用法。我查了字典，没有查到这个用法啊：（

我现在只能理解到，这个句子的意思是computers are..., and modems are...too，为了后面的修饰能够准确而无歧异的修饰modems，所以用了倒装。不过还是不能解释这里so too 用法。