ㄓㄠㄨㄣˊㄒㄧˋㄍㄞˇzhāowén‑xìgǎi

朝闻夕改
zhāowén‑xīgǎiㄓㄠ ㄨㄣˊ ㄒㄧ ㄍㄞˇ
  1. 早晨別人指出自己缺點晚上改正改過 朝聞夕改難能可貴」。

lit. heard in the morning and changed by the evening, to correct an error very quickly (idiom)​