磨杵成针 (磨杵成針) mó chǔ chéng zhēn

mó chǔ chéng zhēn set phrase to grind an iron bar down to a fine needle; to persevere in a difficult task; to study diligently
Domain: Idiom 成语 , Subdomain: , Concept:
Notes: (CC-CEDICT '磨杵成針')