Context is Key
Irregular verbs do not change in every situation.
It typically depends on the ending you attach. Endings starting with a consonant often keep the original stem, while endings starting with a vowel usually trigger the change.
You cannot guess if a word is irregular just by looking at its dictionary form. You must learn common words alongside their conjugated forms.
Reviewing ㄷ, ㅂ, and ㅅ
When followed by a vowel
ㄷ changes to ㄹ: 듣다 → 들어요
ㅂ changes to 우/오: 춥다 → 추워요
ㅅ drops: 짓다 → 지어요
Remember that regular verbs with the same bottom letters keep their shape. For example:
Dictionary Form · Conjugated Form
닫다 · 닫아요
입다 · 입어요
씻다 · 씻어요
Reviewing 르, ㅎ, and ㄹ
Specific Vowel and Consonant Changes
르 adds an extra ㄹ: 부르다 → 불러요
ㅎ drops and changes the vowel: 파랗다 → 파래요
ㄹ drops before ㄴ, ㅂ, or ㅅ: 살다 → 사세요
Regular verbs with similar shapes do not undergo these changes. For example, 좋다 (to be good) keeps its shape and simply becomes 좋아요 .
Common Mistake: Over-applying Rules
Because irregular verbs are so frequently used, beginners sometimes accidentally apply irregular rules to regular verbs.
닫다 (to close) is regular. Do not say 달아요 . It is 닫아요 .
씻다 (to wash) is regular. Do not drop the ㅅ. It is 씻어요 .
Always learn verbs as a pair: the dictionary form and its basic present tense form. This removes the guesswork.
Quick review
don't over-apply
learn standard forms