bô-chhái-kang無彩工

to waste effort

to waste effort; to be in vain; to lose one's pains

English Wiktionary, “無彩工” (CC BY-SA 4.0) — https://en.wiktionary.org/wiki/%E7%84%A1%E5%BD%A9%E5%B7%A5 · confidence: Medium (Wiktionary)