H-Weakening (ㅎ 탈락)
ㅎ as a 받침 disappears before vowel-initial syllables. Combined with ㄴ or in ㄴㅎ/ㄹㅎ clusters, it also weakens.
ㅎ is the most slippery consonant in Korean. As an initial consonant it sounds like English 'h', but as a 받침 (final consonant) it weakens or disappears entirely in most environments. When followed by a vowel-initial syllable, it drops out — 좋아요 (good) is pronounced 'jo-a-yo', not 'jot-a-yo'. When followed by a plain consonant, it aspirates that consonant instead of being pronounced itself.
Example: 좋다 (to be good) is pronounced 'jo-ta' because the final ㅎ of 좋 combines with the ㄷ of 다 to produce ㅌ (aspirated t). 어떻게 (how) follows the same pattern. The general principle: ㅎ rarely survives as itself when it meets another consonant — it either disappears or gets absorbed into the next consonant as aspiration. Learners who try to pronounce every ㅎ explicitly end up sounding stilted; trust the rules and let ㅎ vanish.
ㅎ 탈락 — ㅎ Drops Before Vowels
When ㅎ is the 받침 and the next syllable starts with ㅇ (silent/vowel), the ㅎ completely disappears. 좋아요: 좋[joh]+아요 → [조아요]. 놓아요: 놓[noh]+아요 → [노아요].
ㄴㅎ Cluster — ㅎ Also Drops
In double-받침 clusters ㄴㅎ (않, 많) and ㄹㅎ (싫, 옳), ㅎ drops before vowels. 많아요: 많(ㄴ+ㅎ)+아요 → [마나요]. 않아요: 않(ㄴ+ㅎ)+아요 → [아나요].
How It Works
ㅎ is the weakest consonant in Korean — it is essentially just breath — and weak sounds are the first to disappear when speech speeds up. The rule here is the formal version of that tendency: when ㅎ sits in the 받침 position and the next syllable begins with ㅇ, the ㅎ simply drops out and normal linking takes over.
So 좋아요 is written 좋 + 아요 but spoken [조아요]. The ㅎ vanishes entirely; it does not move forward the way ㄱ would in 먹어요. Nothing takes its place, so the vowels end up adjacent. 넣어요 → [너어요] and 놓아요 → [노아요] behave identically.
The clusters ㄴㅎ and ㄹㅎ work the same way with one extra detail. In 많아요, the 받침 is ㄴ + ㅎ. The ㅎ drops, and the surviving ㄴ then links forward normally by 연음화: [마나요]. 않아요 → [아나요] follows exactly this path, as does 싫어요 → [시러요] with ㄹ. So these are not a new rule — they are ㅎ-dropping followed by the linking you already learned in Lesson 1-7.
The opposite behaviour is worth knowing exists: when ㅎ meets a plain consonant rather than a vowel, it does not vanish but merges to create an aspirated consonant, which is why 좋다 is [조타] rather than [조다].
Where You'll Hear It
좋아요 is one of the most useful words in the language. It means 'good', 'I like it', and functions as general agreement — and with 좋아해요 it becomes how you say you like something or someone. You will say it dozens of times a day, and it is never pronounced with the ㅎ.
많아요 ('there are many') is equally common, especially in the fixed phrase 사람이 많아요 ('it's crowded'), which you will hear and use constantly in Seoul. 않아요 is the standard negation ending, so every negative sentence built with -지 않다 runs through this rule: 가지 않아요 → [가지 아나요].
The consequence for learners is that some of the highest-frequency words in Korean look nothing like they sound. Someone who has only read 좋아요 may not connect it to the [조아요] they keep hearing. And because these words carry so much conversational weight — agreement, preference, negation — failing to link them is one of the fastest ways to sound stilted, even when every individual sound is correct.
Cultural & Language Note
ㅎ is the weakest consonant in Korean and behaves accordingly — it drops, merges, and softens far more readily than any other. This is a common fate for h-sounds across languages: the same weakening turned Latin 'hora' into French 'heure' with a silent h. Korean simply happens to write the ㅎ that it no longer fully pronounces.
Common Mistakes to Avoid
Pronouncing the ㅎ in 좋아요 gives 'jo-ha-yo', which sounds distinctly foreign; it is 'jo-a-yo'. The opposite error also happens: learners drop ㅎ where it should instead merge into aspiration. In 좋다 the ㅎ does not vanish — it combines with ㄷ to give 'jo-ta'. Dropping versus merging depends on what follows, so check whether the next sound is a vowel or a plain consonant.
How to Practice This Lesson
Anchor the rule to three words rather than learning it abstractly: 좋아요, 많아요, 않아요. These three cover agreement, quantity and negation, which is most of what you need the rule for. Say each twenty times in its linked form until [조아요], [마나요] and [아나요] feel like single units rather than assembled syllables.
Then practise the contrast that trips people up: 좋아요 [조아요] versus 좋다 [조타]. Same stem, vowel after versus consonant after, completely different outcomes. Saying them back to back makes the conditioning stick.
A useful habit at this stage is to write the spoken form in brackets next to any new word containing a ㅎ 받침. You are building a second mental entry for each word — one for reading, one for listening — and doing it deliberately is much faster than waiting for it to happen by exposure.