问题
选择题
____ with the size of the whole earth, the highest mountain doesn’t seem high at all.
A．To compare
B．while comparing
C．It comparing
D．when compared
答案
答案：D
考查省略句。当状语从句的主语与主句主语一致的时候，可以把主语与系动词省略，构成省略句。本题when后面省略了the highest mountain is compared.句意：当最高的山与整个地球进行比较时，最高的山也一点都不高了。