惩前毖后 chéng qián bì hòu

DEFINITIONS

  1. lit. to punish those before to prevent those after (idiom); to criticize former mistakes firmly to prevent them happening again

CHARACTERS

惩 chéng punish, reprimand; warn
前 qián in front, forward; preceding
毖 bì guard against, take care; caution
后 hòu queen, empress, sovereign; (simp. for 後) behind, rear, after