잘하다
jalhada · TOPIK 1
to do well, to be good at
🏆 잘하다 = 잘 (well) + 하다 (to do): literally to do well
잘 is the adverb well, and 하다 is the all-purpose verb to do. Glue them together and you get to do well, to be good at. Contrast with 못하다 (못 = cannot + 하다), which means to be bad at.