______ with the size of the whole earth, the highest mountains do not seem high at all.

问题描述:

______ with the size of the whole earth, the highest mountains do not seem high at all.
A. If you compare
B. Compare them
C. When compared
D. A comparison
为什么选C其他选项错在哪里

A.错在前后主语不一致,前面说you,后面说mountain
B.Compare 是动词原形,没有主语
D.A comparison 是名词,可以用来作主语,但是前半句又没有谓语了