appear and disappear without regularity
This idiom is pronounced ch ū m ò B ù ch á ng, which means that the appearance and disappearance are irregular and unpredictable.
explain
The appearance and disappearance are irregular and unpredictable.
source
Li Gang of the Song Dynasty wrote in his treatise on defending thieves with the Prime Minister: "this thief is not the ratio of land group thieves. According to the fact that the lake is surrounded by thousands of miles, it is not uncommon."
Examples
There are pirates in the lake. Dai Mingshi's epitaph of Zhang Gongmu
usage
Used as a predicate or attribute; used of mysterious people or things
Chinese PinYin : chū mò bù cháng
appear and disappear without regularity
pay attention to the interests of the whole. gù quán dà jú
fear the enemy as if he were a tiger. wèi dí rú hǔ
injure both the state and the people. bìng guó yāng mín