Liaison 연음: Batchim Moves to the Next Syllable

Of all Korean sound rules, liaison (연음) is the one you meet most — it fires in almost every sentence you will ever say. The mechanics are simple: when a syllable ends in a batchim (a final consonant) and the next syllable begins with the silent onset ㅇ — that is, with a vowel — the batchim slides forward and becomes that next syllable's onset. 한국어 is not read block-by-block as "han-guk-eo"; the ㄱ of 국 glides onto the 어 and you get [한구거], han-gu-geo. Once you expect this, Korean stops sounding choppy and starts to flow.

The core move

Written Korean is laid out in neat square blocks, and it is tempting to pronounce each block as a self-contained unit. Liaison is the rule that breaks that habit. Any single batchim, when a vowel follows, leaves its own block and re-syllabifies onto the next one.

한국어 is spelled 한 + 국 + 어, but the ㄱ of 국 has nothing to hold it in place once a vowel is waiting next door — it relinks, giving [한구거]. The written boundary between 국 and 어 is a spelling boundary; the sound runs straight across it.

Two liaisons here: 음악 → [으막] (the ㅁ of 음 slides onto the silent-ㅇ onset of 악; the final ㄱ of 악 has no vowel after it, so it stays put), and 들으면서 → [드르면서] (the ㄹ of 들 slides onto the 으). The written blocks 음·악 and 들·으 are not where the syllables actually break when spoken.

밥을 → [바블], 먹어요 → [머거요]. The object particle 을 begins with a vowel, so the ㅂ of 밥 glides onto it. This is why particles are the great engine of liaison: they nearly all begin with a vowel, so nearly every noun-plus-particle relinks.

The half that makes liaison useful: it restores the hidden consonant

Liaison is not only mechanical; it is diagnostic. Recall from the sound inventory that many consonants neutralize at the end of a syllable — 옷 ("clothes") is pronounced [옫], 꽃 ("flower") is [꼳], their true ㅅ and ㅊ flattened to a plain [t]. But the instant a vowel follows and the consonant relinks, its real value comes back:

옷이 is [오시] — the ㅅ links across as a clean [s], not the neutralized [t]. In isolation the word gave you [옫] and hid its ㅅ; the particle form hands it right back.

꽃을 is [꼬츨] — the ㅊ resurfaces, sharp and unmistakable, though 꽃 alone is only [꼳]. This is the practical payoff: you learn a noun's true final consonant from its particle-attached form, not from its dictionary shape. Say a word with 이 or 을 and it confesses its real ending.

The two rules interlock cleanly. The seven-sound neutralization applies before a pause or a consonant; liaison applies before a vowel and undoes the neutralization. Same word, two environments, two outcomes — 꽃 [꼳] alone, 꽃이 [꼬치] with a vowel.

Only a single batchim links this simply

Everything above concerns a single final consonant. When a syllable ends in a two-consonant cluster (a 겹받침 like ㄺ, ㄼ, ㅄ), the cluster splits — one member stays behind as the coda, the other links forward — and there are a few tensing wrinkles. That case is important enough to have its own treatment: see double-batchim resyllabification, which also handles the one final that refuses to link at all, the batchim ㅇ.

Across a word boundary, the neutralized value links

Here is the subtle point that separates a native-sounding reader from a careful-but-foreign one, and that most textbooks skip. Liaison within a single word — a noun and its particle, a stem and its ending — links the underlying (real) consonant: 옷이 [오시], 꽃을 [꼬츨], 밭에 [바테]. But when the vowel that follows belongs to a separate, independent word, the batchim first neutralizes to its seven-sound value, and only then links.

Say 꽃이 (flower + particle) and you get [꼬치], with the true ㅊ. But 꽃 위 ("flower-top," two separate words) is [꼬뒤] — the ㅊ first flattens to [t], and it is that neutralized [t] that links onto 위, surfacing as [d]. Not ×[꼬취]. The same split shows up in 옷 안 ("inside the clothes") → [오단], not [오산], and 밭 아래 ("below the field") → [바다래], not [바타래]. The rule of thumb: link the real consonant across a particle or ending; link the neutralized consonant across a word boundary.

(You will notice the romanization above writes 꽃 위에 as "kkot wie," keeping the block boundary, and the actual linked pronunciation [꼬뒤에] appears in the prose bracket. That is deliberate: the reading aid shows you the words, the bracket shows you the sound.)

Why English speakers block liaison — and how to unblock it

English orthography and Korean orthography both draw word boundaries, and English speakers instinctively honor them: they say the noun, insert a tiny glottal catch, and then say the particle — "ot · eul," "bap · eul." That little catch is precisely what stops the glide. Korean wants no seam at all between the batchim and the following vowel.

시간이 is one smooth [시가니] and 있으면 is [이쓰면] — two liaisons in a row, no pauses, no catches. If you break 시간 · 이 apart with a glottal stop, you sound like you are reading a spelling list, not speaking. Glide the ㄴ straight into the 이 and both the linking and the flow come for free.

옷을 is a seamless [오슬] — not "ot … eul" with a pause and a neutralized [t]. And 입고 → [입꼬] shows the flip side: no vowel follows the ㅂ there, so it stays put and the ㄱ tenses; liaison only fires into a vowel.

For the sister rule that governs the batchim ㅎ (which, uniquely, drops rather than linking), see ㅎ before a vowel. For the block-by-block mechanics laid out slowly, see batchim resyllabification.

Common Mistakes

1. Pronouncing each written block separately. The classic beginner rhythm reads 한국어 as "han · guk · eo." The ㄱ must relink.

• ✗ 한국어 read as "han-guk-eo," three sealed blocks.
• ✓ 한국어 [한구거] — the ㄱ glides onto 어.

2. Inserting a glottal catch before the particle. A tiny stop between noun and particle blocks the glide and outs you as a non-native reader.

• ✗ 밥을 said as "bap · eul" with a catch.
• ✓ 밥을 [바블] — one seamless glide.

3. Carrying the neutralized sound into the linked form. Because 꽃 alone is [꼳], learners keep the [t] and say "[꼳이]." The vowel restores the real ㅊ.

• ✗ 꽃이 read as "kkot-i."
• ✓ 꽃이 [꼬치] — the true ㅊ returns.

4. Linking the real consonant across a word boundary. Within a word you link the underlying consonant, but across two separate words you link the neutralized one.

• ✗ 꽃 위 read as "[꼬취]," treating it like 꽃이.
• ✓ 꽃 위 [꼬뒤] — ㅊ first neutralizes to [t], then links as [d].

5. Learning a noun's ending only from its bare form. Memorize 꽃 as "[꼳]" and you will mis-store it as ending in [t] and mangle every inflected form. Learn it from 꽃이 [꼬치].

Key Takeaways

• Liaison (연음) slides a single batchim forward onto a following vowel (the silent ㅇ): 한국어 [한구거], 밥을 [바블], 음악 [으막].
• A written block is a spelling unit, not a pronunciation unit — glide across the boundary, never pause at it.
• Liaison restores a neutralized final to its true value: 옷이 [오시], 꽃을 [꼬츨]. So a noun's particle form reveals its real ending.
• Within a word, the underlying consonant links (꽃이 [꼬치]); across a word boundary, the neutralized consonant links (꽃 위 [꼬뒤]).
• The great blocker is the English glottal catch at word boundaries. Kill the catch and both the linking and the flow appear.