Not only___ polluted,but also __ dirty.请问正确答案是什么?为什么?

问题描述:

Not only___ polluted,but also __ dirty.请问正确答案是什么?为什么?
A.is the air,are rivers
B.is the air,.rivers are
C.the air is,rivers are
D.the air is ,are rivers

B
Not only 置于句首时,该句中的主谓倒装,but also后的语序不倒装