Irregular stems 르 and ㅎ, and the full irregular table

A2 불규칙 활용 르·ㅎ와 전체 정리 39 / 68

In short

Two more stem classes finish the irregular picture. A 르 stem doubles its ㄹ before an 아/어 ending: 모르다 -> 몰라요 (mollayo, I don’t know), 부르다 -> 불러요 (bulleoyo, I sing). A ㅎ adjective drops its ㅎ and turns the vowel into ㅐ: 그렇다 -> 그래요 (geuraeyo, that’s right), 빨갛다 -> 빨개요 (ppalgaeyo, it’s red). As always, the look-alikes stay regular: 따르다 -> 따라요, 좋다 -> 좋아요.

The rule

Step 1 - 르 불규칙: the ㄹ doubles, and the vowel before 르 chooses 아/어

When a stem ending in 르 meets an 아/어 ending, the 으 of 르 disappears, a ㄹ is added as a 받침 to the syllable in front, and the ending itself starts with ㄹ - so you hear a double ㄹ. Which vowel? Look at the vowel in the syllable before 르: ㅏ or ㅗ takes 라, everything else takes 러.

모르 + 아요 -> 몰라요 (ㅗ before 르 -> 라) - 부르 + 어요 -> 불러요 (ㅜ before 르 -> 러)

Before a -(으)- ending or a plain consonant, a 르 stem is completely regular, because there is no 아/어 to trigger the doubling: 모르면 (moreumyeon), 모릅니다 (moreumnida). The modifier endings behave the same way - 모르는 (moreuneun), 다른 (dareun), 빠른 (ppareun) - and the ㄴ of -는 takes nothing away here, because a 르 stem has no ㄹ 받침 for the ㄹ row’s deletion rule to remove.

Step 2 - The regular 으-stems that only look like 르 stems

따르다 (ttareuda, follow, pour) and 들르다 (deulleuda, drop by) end in 르 too, but they are ordinary 으-elision stems (lesson 10): the 으 simply drops and no extra ㄹ is added. So 따르다 -> 따라요 (one ㄹ), while the 르-irregular 다르다 -> 달라요 (two ㄹ). The added ㄹ is the whole difference. (Watch 들르다 -> 들러요: the ㄹ 받침 in 들 is already part of the stem, so nothing was doubled - compare the genuinely 르-irregular 흐르다 -> 흘러요, where the ㄹ of 흘 is new.)

Step 3 - ㅎ 불규칙: drop the ㅎ, and the vowel becomes ㅐ

Almost every ㅎ-final adjective is irregular. Two things happen at once:

  • Before an 아/어 ending, the ㅎ drops and the vowel merges to ㅐ: 그렇 + 어요 -> 그래요, 빨갛 + 아요 -> 빨개요. A stem whose vowel is ㅑ gives ㅒ: 하얗 + 아요 -> 하얘요 (hayaeyo, it’s white).
  • Before a -(으)- ending, the ㅎ and the 으 both drop: 그렇 + (으)면 -> 그러면 (geureomyeon, if so), 그렇 + (으)ㄴ -> 그런 (geureon, such).

Before a plain consonant nothing changes in the spelling: 그렇고 (geureoko), 그렇습니다 (geureoseumnida).

Step 4 - The ㅎ regulars: 좋다, 넣다, 놓다

The class has a clean boundary: ㅎ 불규칙 is an adjective-only class. Every ㅎ-final verb is regular (넣다, 놓다, 낳다, 쌓다), and among the ㅎ-final adjectives 좋다 is the single regular one. These keep the ㅎ in spelling, keep the 으, and never change the vowel: 좋다 -> 좋아요 (joayo), 넣다 -> 넣어요 (neoeoyo, put in), 놓다 -> 놓아요 (noayo, put down). The ㅎ-irregular pattern is for the colours and the 이렇다/그렇다/저렇다/어떻다 family - never for these three.

Forms & patterns

르 불규칙 - and its regular 으-stem look-alikes:

Dictionary form해요 formPast-(으)면Vowel rule
모르다 (not know)몰라요 (mollayo)몰랐어요 (mollasseoyo)모르면 (moreumyeon)ㅗ -> 라
빠르다 (be fast)빨라요 (ppallayo)빨랐어요 (ppallasseoyo)빠르면 (ppareumyeon)ㅏ -> 라
부르다 (call, sing)불러요 (bulleoyo)불렀어요 (bulleosseoyo)부르면 (bureumyeon)ㅜ -> 러
다르다 (be different)달라요 (dallayo)달랐어요 (dallasseoyo)다르면 (dareumyeon)ㅏ -> 라
고르다 (choose)골라요 (gollayo)골랐어요 (gollasseoyo)고르면 (goreumyeon)ㅗ -> 라
흐르다 (flow)흘러요 (heulleoyo)흘렀어요 (heulleosseoyo)흐르면 (heureumyeon)ㅡ -> 러
regular 따르다 (follow, pour)따라요 (ttarayo)따랐어요 (ttarasseoyo)따르면 (ttareumyeon)single ㄹ
regular 들르다 (drop by)들러요 (deulleoyo)들렀어요 (deulleosseoyo)들르면 (deulleumyeon)no ㄹ added

ㅎ 불규칙 - and its three regular look-alikes:

Dictionary form해요 formPast-(으)ㄴ modifier-(으)면
그렇다 (be so)그래요 (geuraeyo)그랬어요 (geuraesseoyo)그런 (geureon)그러면 (geureomyeon)
이렇다 (be like this)이래요 (iraeyo)이랬어요 (iraesseoyo)이런 (ireon)이러면 (ireomyeon)
어떻다 (be how)어때요 (eottaeyo)어땠어요 (eottaesseoyo)어떤 (eotteon)어떠면 (eotteomyeon)
빨갛다 (be red)빨개요 (ppalgaeyo)빨갰어요 (ppalgaesseoyo)빨간 (ppalgan)빨가면 (ppalgamyeon)
파랗다 (be blue)파래요 (paraeyo)파랬어요 (paraesseoyo)파란 (paran)파라면 (paramyeon)
하얗다 (be white)하얘요 (hayaeyo)하얬어요 (hayaesseoyo)하얀 (hayan)하야면 (hayamyeon)
regular 좋다 (be good)좋아요 (joayo)좋았어요 (joasseoyo)좋은 (joeun)좋으면 (joeumyeon)
regular 넣다 (put in)넣어요 (neoeoyo)넣었어요 (neoeosseoyo)넣은 (neoeun)넣으면 (neoeumyeon)
regular 놓다 (put down)놓아요 (noayo)놓았어요 (noasseoyo)놓은 (noeun)놓으면 (noeumyeon)

The full seven-class table - one row per class, three ending types, plus the regular look-alike:

ClassExample+ 아/어 (해요)+ -(으) (면)+ ㅂ/ㅅ/ㄴRegular look-alike
ㅂ덥다 (deopda)더워요 (deowoyo)더우면 (deoumyeon)덥습니다 (deopseumnida)입다 -> 입어요 (ibeoyo)
ㄷ듣다 (deutda)들어요 (deureoyo)들으면 (deureumyeon)듣습니다 (deutseumnida)받다 -> 받아요 (badayo)
ㅅ짓다 (jitda)지어요 (jieoyo)지으면 (jieumyeon)짓습니다 (jitseumnida)웃다 -> 웃어요 (useoyo)
ㄹ살다 (salda)살아요 (sarayo)살면 (salmyeon)삽니다 (samnida)(all ㄹ stems behave alike)
으쓰다 (sseuda)써요 (sseoyo)쓰면 (sseumyeon)씁니다 (sseumnida)바쁘다 -> 바빠요 (bappayo)
르모르다 (moreuda)몰라요 (mollayo)모르면 (moreumyeon)모릅니다 (moreumnida)따르다 -> 따라요 (ttarayo)
ㅎ그렇다 (geureota)그래요 (geuraeyo)그러면 (geureomyeon)그렇습니다 (geureoseumnida)좋다 -> 좋아요 (joayo)

Read the table as one question: does an 아/어 or an 으 reach the stem? If yes, the class fires; if only a plain consonant arrives (-고, -지만, -습니다 aside from the ㄹ row), the stem is written straight from the dictionary.

Examples

  • 저는 그 사람을 잘 몰라요. (Jeoneun geu sarameul jal mollayo.) - I don’t know that person well.
  • 이 기차는 정말 빨라요. (I gichaneun jeongmal ppallayo.) - This train is really fast.
  • 친구가 노래를 불러요. (Chinguga noraereul bulleoyo.) - My friend is singing a song.
  • 제 생각은 조금 달라요. (Je saenggageun jogeum dallayo.) - My opinion is a little different.
  • 저는 규칙을 잘 따라요. (Jeoneun gyuchigeul jal ttarayo.) - I follow the rules well.
  • 그래요, 저도 그렇게 생각해요. (Geuraeyo, jeodo geureoke saenggakaeyo.) - That’s right, I think so too.
  • 이 사과는 정말 빨개요. (I sagwaneun jeongmal ppalgaeyo.) - This apple is really red.
  • 오늘 하늘이 아주 파래요. (Oneul haneuri aju paraeyo.) - The sky is very blue today.
  • 요즘 날씨가 어때요? (Yojeum nalssiga eottaeyo?) - How’s the weather these days?

Common mistakes

  • 다르어요 (dareueoyo) -> 달라요 (dallayo) - 다르다 is 르-irregular, so the ㄹ doubles before 아/어. It is not a plain 으-stem.
  • 딸라요 (ttallayo) -> 따라요 (ttarayo) - 따르다 is a regular 으-stem, so only a single ㄹ appears. Doubling belongs to 다르다 -> 달라요, not here.
  • 그렇어요 (geureoeoyo) -> 그래요 (geuraeyo) - ㅎ-irregular: the ㅎ drops and the vowel becomes ㅐ. Never keep the ㅎ before a vowel.
  • 좋애요 (joaeyo) -> 좋아요 (joayo) - 좋다 is regular. The ㅎ-irregular vowel change is only for colours and the 그렇다 family, never for 좋다/넣다/놓다.
  • 빨갛은 (ppalga-eun) -> 빨간 (ppalgan) - before the modifier -(으)ㄴ the ㅎ and the 으 both drop.

Tips

  • The 르 vowel test: look at the vowel in the syllable before 르. ㅏ or ㅗ gives 라 (몰라, 빨라, 달라, 골라); anything else gives 러 (불러, 흘러). The ㄹ always doubles.
  • Single ㄹ vs double ㄹ is the entire regular/irregular split: 따르다 -> 따라요 (one), 다르다 -> 달라요 (two). Memorise the pair and you will never write *딸라요.
  • ㅎ-irregular in one line: drop the ㅎ, and the ending vowel turns to ㅐ. Only 좋다 and the ㅎ-final verbs (넣다, 놓다, 낳다, 쌓다) keep the ㅎ and stay regular.
  • Don’t confuse 어때요 (from 어떻다, how is it?) with the adverb 어떻게 (eotteoke, how, in what way) - same root, different jobs.