机关算尽太聪明，反算了卿卿性命
jī​guān​suàn​jìn​tài​cōng​ming, fǎn​suàn​le​qīng​qīng​xìng​mìng

over-calculating backfires

机关算尽太聪明，反算了卿卿性命 (機關算盡太聰明，反算了卿卿性命) jī​guān​suàn​jìn​tài​cōng​ming, fǎn​suàn​le​qīng​qīng​xìng​mìng
over-calculating backfires
If one is too calculating, it will be the cause of one's own undoing (famous line in "A Dream of Red Mansions").

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