To lead to endless troubles or consequences in the future; to sow the seeds of future calamities.
如果不及时修补屋顶的漏洞，等到雨季来临，可能会后患无穷
If the leak in the roof isn't fixed in time, when the rainy season arrives, it could lead to endless troubles.
Era:
Ancient
Frequency:
Story:
In the first year of Jian'an (196 AD) during Emperor Xian's reign, Liu Bei, the Governor of Xuzhou, sought refuge with Cao Cao after being attacked by Yuan Shu. Cao Cao outwardly treated Liu Bei with importance, allowing him to recruit soldiers and horses to attack Yuan Shao in Xuzhou.
However, his strategist Guo Jia, upon hearing that Liu Bei was allowed to leave, warned that it would surely lead to endless future troubles.
Cao Cao immediately realized this and led his troops to attack Xuzhou. Liu Bei promptly sought refuge with Yuan Shao.
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