ˇㄧㄠˋzhǐyàoㄍㄨㄥㄈㄨgōngfūㄕㄣshēnㄊㄧㄝˇㄔㄨˇtiěchǔㄇㄛˊㄔㄥˊmóchéngㄓㄣzhēn

只要功夫深,铁杵磨成针
zhǐyào gōngfu shēn, tiěchǔ móchéng zhēnㄓˇ ㄧㄠˋ ㄍㄨㄥ ˙ㄈㄨ ㄕㄣ,ㄊㄧㄝˇ ㄔㄨˇ ㄇㄛˊ ㄔㄥˊ ㄓㄣ
  1. 只要花費時間心力比喻只要苦功持之以恆事情 精通學問技藝沒有捷徑只要功夫深,鐵杵磨成針」。

If you work at it hard enough, you can grind an iron bar into a needle., cf idiom 磨杵成針, to grind an iron bar down to a fine needle (idiom)​; fig. to persevere in a difficult task, to study diligently