The most common question a learner has in front of a new verb is blunt and practical: this stem ends in ㄷ (or ㅅ, ㅂ, ㅎ, 르) — does it conjugate irregularly or not? This page answers it with one lookup table. The organizing principle is the minimal pair: each irregular verb sits directly beside a regular verb that ends in the same consonant, so your eye can compare them and absorb the one fact that matters — a stem's final consonant is only a hint, never a rule. Irregularity is a lexical property, memorized per word. This sheet is the card that saves you from guessing.
The master table
Read it in blocks. Within each block the final consonant is held constant, and the "Irregular?" column is the whole story. The -아/어요 form shows what the difference actually produces.
| Verb | Final | Irregular? | -아/어요 | What happens |
|---|---|---|---|---|
| 듣다 (listen) | ㄷ | IRREGULAR | 들어요 deureoyo | ㄷ → ㄹ before a vowel |
| 닫다 (close) | ㄷ | regular | 닫아요 dadayo | ㄷ just liaises |
| 받다 (receive) | ㄷ | regular | 받아요 badayo | ㄷ just liaises |
| 믿다 (believe) | ㄷ | regular | 믿어요 mideoyo | ㄷ just liaises |
| 짓다 (build) | ㅅ | IRREGULAR | 지어요 jieoyo | ㅅ drops entirely |
| 웃다 (laugh) | ㅅ | regular | 웃어요 useoyo | ㅅ just liaises |
| 씻다 (wash) | ㅅ | regular | 씻어요 ssiseoyo | ㅅ just liaises |
| 벗다 (take off) | ㅅ | regular | 벗어요 beoseoyo | ㅅ just liaises |
| 덥다 (be hot) | ㅂ | IRREGULAR | 더워요 deowoyo | ㅂ → 우, fuses to 워 |
| 입다 (wear) | ㅂ | regular | 입어요 ibeoyo | ㅂ just liaises |
| 잡다 (grab) | ㅂ | regular | 잡아요 jabayo | ㅂ just liaises |
| 좁다 (be narrow) | ㅂ | regular | 좁아요 jobayo | ㅂ just liaises |
| 그렇다 (be so) | ㅎ | IRREGULAR | 그래요 geuraeyo | ㅎ drops, fuses to 애 |
| 좋다 (be good) | ㅎ | regular | 좋아요 joayo | ㅎ kept in spelling |
| 모르다 (not know) | 르 | 르-IRREGULAR | 몰라요 mollayo | ㄹ doubles: 모ㄹ + 라 |
| 부르다 (call/sing) | 르 | 르-IRREGULAR | 불러요 bulleoyo | ㄹ doubles: 부ㄹ + 러 |
| 따르다 (follow/pour) | 르 | regular (으-drop) | 따라요 ttarayo | only the 으 drops |
| 치르다 (pay/undergo) | 르 | regular (으-drop) | 치러요 chireoyo | only the 으 drops |
Look at any block and the lesson is the same: the final consonant tells you which irregular pattern a verb could follow, but not whether it does. 듣다 and 닫다 both end in ㄷ; one mutates and one does not. 짓다 and 웃다 both end in ㅅ; one drops the ㅅ and one keeps it. Nothing in the spelling predicts the split — you know it because you learned the word.
저는 출근할 때 항상 음악을 들어요.
jeoneun chulgeunhal ttae hangsang eumageul deureoyo
I always listen to music on my commute. (듣다, IRREGULAR → 들어요)
추우니까 문 좀 닫아 주세요.
chu-unikka mun jom dada juseyo
It's cold, so please close the door. (닫다, regular → 닫아요, not ×달아요)
ㅅ that stays vs ㅅ that vanishes
The ㅅ block is the one where the eye most wants to over-apply the irregular. 짓다 "build" really does drop its ㅅ (지어요), but 웃다 "laugh," 씻다 "wash," and 벗다 "take off" keep theirs and simply liaise. The result is a genuine minimal pair in sound: irregular 지어요 has no [s] at all, while regular 웃어요 is pronounced [우서요] with the ㅅ carried onto the next syllable.
삼촌이 시골에 집을 직접 지었어요.
samchoni sigore jibeul jikjeop jieosseoyo
My uncle built a house in the countryside himself. (짓다, IRREGULAR → 지었어요)
그 얘기를 듣고 다들 크게 웃었어요.
geu yaegireul deutgo dadeul keuge useosseoyo
Everyone burst out laughing at that story. (웃다, regular → 웃었어요, ㅅ kept)
ㅂ that softens vs ㅂ that stays
Same trap with ㅂ. 덥다 "be hot" softens its ㅂ to 우 (더워요), but 입다 "wear," 잡다 "grab," and 좁다 "be narrow" keep theirs. Note the rough tendency, useful but not a law: many ㅂ-irregulars are descriptive verbs about sensation and weather (춥다, 맵다, 무겁다), while a lot of the regular ㅂ-verbs are action verbs (입다, 잡다) — a hint worth having, though 좁다 (a regular adjective) and 굽다 "grill" (an irregular verb) each break it.
여름엔 서울이 정말 더워요.
yeoreumen Seouri jeongmal deowoyo
Seoul gets really hot in summer. (덥다, IRREGULAR → 더워요)
오늘은 쌀쌀해서 코트를 입어요.
oneureun ssalssalhaeseo koteureul ibeoyo
It's chilly today, so I'm wearing a coat. (입다, regular → 입어요, not ×이워요)
The 르 fork, and the homograph that ends the sheet
The last block is a fork, not a pair: most 르-final verbs are 르-irregular (the ㄹ doubles: 모르다 → 몰라요, 부르다 → 불러요), but a handful — 따르다 "follow/pour," 치르다 "pay/undergo," 들르다 "drop by" — are plain 으-drop regulars, so only the ㅡ elides (따라요, 치러요). And the whole point of this page lands hardest on a homograph: 묻다.
| Spelled | Meaning | Irregular? | -아/어요 |
|---|---|---|---|
| 묻다 | ask | IRREGULAR (ㄷ→ㄹ) | 물어요 (mureoyo) |
| 묻다 | bury | regular | 묻어요 (mudeoyo) |
Two words spelled identically, ending in the same ㄷ, and they conjugate differently — because irregularity lives in the word, not the letters. There is no way to read the answer off the spelling; you have to know which 묻다 you mean.
뭐 하나만 물어봐도 돼요?
mwo hanaman mureobwado dwaeyo
Can I ask you just one thing? (묻다 'ask', IRREGULAR → 물어)
강아지가 마당에 뼈를 묻어요.
gang-ajiga madang-e ppyeoreul mudeoyo
The dog buries a bone in the yard. (묻다 'bury', regular → 묻어)
미안해요, 그건 저도 잘 몰라요.
mianhaeyo, geugeon jeodo jal mollayo
Sorry, I don't really know that either. (모르다, 르-IRREGULAR → 몰라요)
저는 그냥 회사 규칙을 따라요.
jeoneun geunyang hoesa gyuchigeul ttarayo
I just follow the company rules. (따르다, regular 으-drop → 따라요, not ×딸라요)
The rule of thumb that actually helps
For English speakers this is the comfortable half of Korean irregularity. English already accepts that sing/sang is irregular while ring the doorbell is whatever it is — you memorized each verb, you did not derive it from spelling. Korean asks the same of you here: the final consonant narrows the possibilities, and the word settles them.
Common Mistakes
1. Treating regular 닫다 as ㄷ-irregular. 닫다 keeps its ㄷ; ×달아요 is a different verb (달다 "hang").
❌ 문 좀 달아 주세요.
Wrong for 'close' — 닫다 is regular → 닫아 주세요. (달다 means 'to hang'.)
✅ 문 좀 닫아 주세요.
mun jom dada juseyo
Please close the door.
2. Treating regular 웃다 as ㅅ-irregular. The ㅅ of 웃다 stays; it does not drop like 짓다's.
❌ 아이가 크게 우어요.
Wrong — 웃다 keeps its ㅅ → 웃어요, not ×우어요 (that would be 짓다's pattern).
✅ 아이가 크게 웃어요.
aiga keuge useoyo
The child is laughing loudly.
3. Treating regular 입다 as ㅂ-irregular. 입다 keeps its ㅂ; only ㅂ-irregulars soften to 우.
❌ 오늘은 코트를 이워요.
Wrong — 입다 is a regular ㅂ-verb → 입어요, not ×이워요 (that's the 덥다 pattern).
✅ 오늘은 코트를 입어요.
oneureun koteureul ibeoyo
Today I'm wearing a coat.
4. Treating regular 따르다 as 르-irregular. 따르다 only drops the 으; it does not double the ㄹ.
❌ 저는 규칙을 딸라요.
Wrong — 따르다 is a regular 으-drop verb → 따라요, not ×딸라요 (that's the 모르다 pattern).
✅ 저는 규칙을 따라요.
jeoneun gyuchigeul ttarayo
I follow the rules.
Key Takeaways
- A stem's final consonant is a hint, not a rule — it tells you which irregular pattern is possible, never whether the verb takes it.
- Minimal pairs prove it: 듣다/닫다 (ㄷ), 짓다/웃다 (ㅅ), 덥다/입다 (ㅂ), 그렇다/좋다 (ㅎ), 모르다/따르다 (르).
- Irregularity is lexical — you memorize it per word, exactly like English sing/sang.
- The homograph 묻다 is the clincher: 'ask' is irregular (물어요), 'bury' is regular (묻어요).
- For an unknown verb, default to REGULAR — over-applying the irregular is the costlier mistake.
Now practice Korean
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Start learning Korean→Related Topics
- ㅂ-Irregular Predicates (ㅂ 불규칙): Full TableTOPIK 2 — The complete lookup grid for the ㅂ-irregular class — stem-final ㅂ fuses into a 우/오 before vowel- and 으-endings (덥다 → 더워요, 더운, 더우니까, 더웠어요), with the two 오-exceptions 돕다·곱다 and a stays-regular warning row (입다·잡다·좁다).
- ㄷ-Irregular Verbs (ㄷ 불규칙): Full TableTOPIK 2 — The complete lookup grid for the ㄷ-irregular class — stem-final ㄷ mutates to ㄹ before vowel- and 으-endings (듣다 → 들어요, 들으니까, 들은, 들었어요) but stays ㄷ before consonants — with the 묻다 homograph split and a stays-regular row (받다·닫다·믿다·얻다).
- ㅅ-Irregular Verbs (ㅅ 불규칙): Full TableTOPIK 2 — The complete lookup grid for the ㅅ-irregular class — stem-final ㅅ drops before vowel- and 으-endings but, unlike ㅂ and ㄷ, leaves an uncontracted two-syllable hiatus (짓다 → 지어요, never ×져요) — with a stays-regular row (웃다·씻다·벗다·빗다).
- 르-Irregular Predicates (르 불규칙): Full TableTOPIK 2 — The complete lookup grid for the 르-irregular class — before an 아/어 ending the 으 of 르 drops and an extra ㄹ pushes back onto the previous syllable (모르다 → 몰라요, 부르다 → 불러요), with 라/러 set by harmony — plus the 으-drop imposters (따르다·치르다) and the separate 러-irregular (이르다·푸르다).
- ㅎ-Irregular Adjectives (ㅎ 불규칙): Full TableTOPIK 3 — The complete reference table for ㅎ-irregular adjectives — 그렇다, 어떻다, and the color words 빨갛다·파랗다·노랗다·까맣다·하얗다 — where a stem-final ㅎ drops before 아/어 and fuses the ending to 애 (그래요, 빨개요), and before 으 the ㅎ and the 으 both vanish (그런, 빨간). With the 좋다 and ㅎ-verb exceptions.