玉不琢不成器 (juk6 bat1 doek3 bat1 sing4 hei3) — jade without chiseling will not become a useful object in Cantonese
jukˍ₆玉batˉ¹不doek˗₃琢batˉ¹不singˎ₄成hei˗₃器Mandarin Pinyin: yu4 bu4 zuo2 bu4 cheng2 qi4
Meaning of 玉不琢不成器
nounjade without chiseling will not become a useful object