41: Korean Irregular Conjugation 1: ㅂ

Learn Korean for Free | Beginner Korean Grammar #41

Why does 춥다 become 추워요, but 춥고 keeps ㅂ? This lesson explains the ㅂ irregular conjugation and its most useful exceptions.

What Does 불규칙 활용 1. ㅂ Mean?

In many adjective and verb stems ending in ㅂ, the ㅂ changes before an ending that begins with a vowel. It usually becomes 우, which combines with -어요 as 워요.

The Rule

춥다 → 추워요, 어렵다 → 어려워요, 덥다 → 더워요. 돕다 and 곱다 usually use 와 before -아요: 도와요, 고와요. Before a consonant-starting ending, ㅂ remains: 춥고, 어렵지만. Some common stems are regular, including 입다, 잡다, 씹다.

Useful Korean Words

KoreanEnglish
춥다to be cold
덥다to be hot
어렵다to be difficult
쉽다to be easy
가볍다to be light
무겁다to be heavy
돕다to help
입다to wear (regular)

Korean Grammar Examples

오늘은 날씨가 추워요.
The weather is cold today.

이 문법은 어렵지만 재미있어요.
This grammar is difficult but interesting.

가방이 가벼워서 좋아요.
I like the bag because it is light.

친구가 숙제를 도와요.
My friend helps with the homework.

겨울에는 따뜻한 옷을 입어요.
I wear warm clothes in winter.

A Short Dialogue

A: 오늘 밖이 추워요? — Is it cold outside today?
B: 네, 아주 추워요. 따뜻하게 입으세요. — Yes, it is very cold. Dress warmly.
A: 이 코트는 무거워요? — Is this coat heavy?
B: 아니요, 아주 가벼워요. — No, it is very light.

A Common Mistake to Avoid

Do not treat every ㅂ-final stem as irregular. 입다 → 입어요, 잡다 → 잡아요, and 씹다 → 씹어요 keep ㅂ. Also remember that ㅂ remains before endings beginning with consonants: 추우고 is incorrect; use 춥고.

Quick Quiz 🎯

Change to -아/어요: ① 춥다 ② 어렵다 ③ 돕다 ④ 입다.

Answers and Explanation

① 추워요 ② 어려워요 ③ 도와요 ④ 입어요. The first three follow the irregular change; 입다 is regular.

Try It Aloud

Read the examples with 불규칙 활용 1. ㅂ slowly, then repeat them at a natural speed. Make two short sentences of your own and record yourself once. Compare the grammar form, spacing, or pronunciation with the model before trying again.

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