I am a beginner, and with my current knowledge, when there is ㅇ after the previous final consonant, the previous final consonant combines with the vowel after ㅇ to pronounce. So, 좋아하다 is supposed to pronounce as 조하하다, but it does not. Is there any sound change rule I don't know?
ㅎ 탈락 (H-dropping)
‘ㅎ(ㄶ, ㅀ)’ 뒤에 모음으로 시작된 어미나 접미사가 결합되는 경우에는, ‘ㅎ’을 발음하지 않는다.
A “ㅎ” (or that in “ㄶ,” “ㅀ”) followed by a conjugation/suffix that doesn’t have an initial consonant, is silent.
- The word: “좋아하다.”
- Its morphemes: “좋-,” “-아,” “하-,” “-다.”
- Since the conjugation “-아” has no initial consonant, the “ㅎ” followed by it is silent.
- The pronunciation: “조아하다” (not “조하하다”).
Basically: if you see a “ㅎ”-ending stem followed by an “ㅇ,” skip the “ㅎ” when you pronounce it.