温故知新 [－－－－]

Jyutping wan1 gu3 zi1 san1
Pinyin wēn gù zhī xīn

Definitions (粵典–words.hk)
  1. 動詞
    重温​經驗​，​而​獲得​新​嘅​體​會
    to gain new understanding by reviewing the old experience