An artist who was recently traveling on a ferry to the southern island discovered a long

An artist who was recently traveling on a ferry to the southern island discovered a long lost antique Greek vase.
A. at random
B. by chance
C. in turn
D. on occasion

A. at random(答案→)B. by chanceC. in turnD. on occasion解析：B　考查介词短语辨析。句意：一位最近乘坐渡船到这个南部岛屿旅行的艺术家偶然发现了一个丢失已久的希腊古董花瓶。at random随意地，随机地；by chance偶然，意外地；in turn依次，轮流；on occasion偶尔，有时。B项符合句意。

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