by thick bamboo and high forest, the ancient city hadn’t been discovered until the 1990s.
A. Surrounding
B. Surround
C. Surrounded
D. Having surrounded
网友回答
A. Surrounding
B. Surround
(答案→)C. Surrounded
D. Having surrounded
解析：动名词表示主动意思，过去分词表示被动含义，这里有被竹子及高树环绕的意思所以选B。被浓密的竹子和高大树木环绕，……