问题补充:
with the size of the whole earth, the biggest ocean does not seem big at all.
A. To compare
B. When comparing
C. Comparing
D. When compared
答案:
A. To compare
B. When comparing
C. Comparing
(答案→)D. When compared
解析:考察分词作状语用法。The biggest ocean与compare之间构成被动关系,使用过去分词。故D正确。可以认为在compared前面省略了it is.