痛ㄊㄨㄥˋ改ㄍㄞˇ前ㄑㄧㄢˊ非ㄈㄟtònggǎi‑qiánfēi

  1. 完全澈底地改正從前的錯誤。例 「痛改前非，重新做人」。

英completely correcting one's former misdeeds (idiom)​; to repent past mistakes and turn over a new leaf, a reformed character