问题补充:
The Diaoyu Islands have been part of China’s territory since ancient times, as important fishing grounds of Taiwan.
A. served
B. to serve
C. serving
D. having served
答案:
A. served
B. to serve
(答案→)C. serving
D. having served
解析:考查现在分词做状语:句意:钓鱼岛自从中国古代就是中国的领土,做为台湾重要的渔业基地。The Diaoyu Islands和serve as是主动关系,用现在分词做状语,选C.