可乘之机

Explanation: Can take advantage of the opportunity. 　　Usage: Partial official; as object; containing derogatory 　　Source: "Jin Shu Chuan Lu usurp": "A raise should calligraphist sharp, advised course of agricultural colonization, to be an opportunity, and then finishes off in one fell swoop." 　　Examples: Song is also a bad idea after Nandu by no ~. (Qing Zhao Yi, "Volume II-sixth and Twenty-Four Histories Conference Notes") Thesaurus:  Watchful waiting Erdong, Can take the gap, haft, fact that may be taken advantage of