Korean Four-Character Idioms
우공이산
愚公移山
Word for word
“the foolish old man moves the mountain”
What it means
Steady effort can achieve the impossible.
When you'd use it
Praising long, patient work.
Example
매일 한 줄씩 쓴 게 책 한 권이 됐어. 우공이산이지.A line a day became a whole book. Steady work moves mountains.