蚁穴坏堤

Explanation: Metaphor not pay attention to little things, it will out of big trouble. The same nest barrier bursts. " 　　Source: Qing Qian "to again revealing" of the five snake bites broken wrist, broken nest embankment, Shi Chen Han who is also the reason why the three pitch. " Thesaurus:  Congqingzhezhou, Yu Shen Zhou plot, An ants' nest Dike, accumulation of straw break the camel's back