青出於藍，而青於藍 [－－于蓝－－－于蓝]

Jyutping cing1 ceot1 jyu1 laam4 ， ji4 cing1 jyu1 laam4
Pinyin qīng chū yú lán ， ér qīng yú lán

Definitions (Wiktionary)
  1. proverb
    the student has surpassed his or her teacher
    (syn.) 更勝於藍, 青过于蓝, 青出于蓝, 而勝於藍, 而胜于蓝, 更胜于蓝, 青出於藍, 青過於藍