열심히
yeolsimhi · TOPIK 1
diligently, hard
🔥 熱心 = hot + heart: doing it with a heated heart, plus adverb ending 히
열심 is the hanja 熱心: 熱 (열, heat) + 心 (심, heart). Adding 히 turns it into an adverb, so 열심히 literally means with a hot heart, i.e. diligently. Same 熱 as in 열 (fever) and same 心 as in 중심 (centre).