Verb Conjugation Basics
Learn how to conjugate Korean verbs into polite present tense (아/어요).
Korean verb conjugation looks intimidating at first, but the polite present tense -아요/어요/여요 follows a small set of patterns once you identify the verb stem. Strip the dictionary form ending -다, and you have the stem. Then apply the vowel-harmony rule: if the last vowel of the stem is ㅏ or ㅗ, attach -아요; otherwise attach -어요. The exception is verbs ending in 하다, which conjugate to 해요.
Examples: 먹다 → 먹어요 (eat), 가다 → 가요 (go — the ㅏ at the end fuses with -아요), 보다 → 봐요 (see — the ㅗ fuses with -아요), 공부하다 → 공부해요 (study). Note that some verbs have stem changes when -아요/어요 attaches; we'll handle those in Lesson 5-5 (irregular verbs). For now, focus on the regular pattern and the 하다 → 해요 transformation. Once you can produce -아요/어요 conjugations on reflex, your Korean output will jump significantly because almost every conversational sentence ends this way.
아/어요 Conjugation Rule
Remove 다 from the dictionary form. If the last vowel of the stem is ㅏ or ㅗ, add 아요. Otherwise, add 어요. 하다 verbs always become 해요.
Vowel Contraction
When the stem vowel and the 아/어 ending overlap, they merge: ㅏ+아→ㅏ (가+아요→가요), ㅗ+아→ㅘ (오+아요→와요), ㅜ+어→ㅝ (주+어요→줘요), ㅣ+어→ㅕ (마시+어요→마셔요).
How It Works
Conjugation into 아요/어요 is a three-step operation. First, remove 다 from the dictionary form to get the stem: 먹다 gives 먹. Second, look at the last vowel of that stem. If it is ㅏ or ㅗ, attach 아요; otherwise attach 어요. Third, apply any contraction that the resulting vowel sequence triggers.
The third step is where most of the apparent irregularity lives, and it is entirely predictable. When two identical vowels meet they collapse into one: 가 + 아요 gives 가요, not 가아요. When different vowels meet they merge into the compound vowel that represents both: ㅗ + ㅏ becomes ㅘ, so 오다 gives 와요. ㅜ + ㅓ becomes ㅝ, so 주다 gives 줘요. ㅣ + ㅓ becomes ㅕ, so 마시다 gives 마셔요. These are exactly the compound vowels you learned back in Level 1, now doing grammatical work.
하다 is the one form you simply memorise: it becomes 해요 rather than following the rule. This is worth the exception because 하다 attaches to an enormous number of nouns to create verbs, so a single memorised form gives you hundreds of conjugations at once.
Note that Korean makes no distinction between 'I eat' and 'I am eating' here — 먹어요 covers both, and context supplies the rest.
Where You'll Hear It
아요/어요 is the form you will speak in. Textbooks often introduce 합니다 first because it looks tidier, but in actual conversation with shopkeepers, colleagues and friends, 해요체 is the default. Choosing to master this ending first is the single most practical decision a beginner can make.
The contracted forms are the ones you hear constantly. 와요 ('come'), 봐요 ('see/watch'), 줘요 ('give'), 마셔요 ('drink') are all contractions, and they appear so frequently that learners often memorise them as standalone words before realising they are regular.
하다 verbs deserve their own attention. 공부해요, 일해요, 운동해요, 요리해요, 전화해요, 사랑해요 — Korean turns almost any activity noun into a verb by attaching 하다, which means your verb vocabulary grows automatically as your noun vocabulary does. When you learn a new activity noun, you have usually learned a verb at the same time.
The same form also serves as a gentle command or suggestion depending on intonation: 여기 앉아요 can mean 'sit here' as easily as 'I sit here', which is why tone matters as much as grammar in spoken Korean.
Cultural & Language Note
The 아/어요 ending is the workhorse of everyday Korean — polite enough for shops, taxis, and colleagues, but not stiff. Korean has several higher formality levels, yet 해요체 covers the vast majority of adult daily interaction. Learners sometimes assume they need the formal 합니다 style to be respectful, but using it with a friendly shopkeeper is like wearing a suit to a coffee shop.
Common Mistakes to Avoid
Vowel contraction is where this breaks down. 가 + 아요 does not become 가아요 but simply 가요; 오 + 아요 becomes 와요; 마시 + 어요 becomes 마셔요. Learners who apply the rule mechanically without contracting produce forms that are grammatically transparent but that no Korean says. 하다 verbs are the most common of all and become 해요, so drill those first.
How to Practice This Lesson
Sort before you drill. Take twenty verbs and split them into three piles: 하다 verbs, ㅏ/ㅗ stems, and everything else. The 하다 pile needs no work beyond 해요. The other two piles each follow one rule. Seeing the verbs grouped this way turns what feels like twenty separate facts into three.
Drill the contractions as whole forms rather than deriving them each time. 와요, 봐요, 줘요, 마셔요, 배워요 should come out without calculation, because in speech you will not have time to work through ㅗ + ㅏ.
Then conjugate ten verbs out loud in one sitting, checking each against the audio. Saying them matters more than writing them — the contractions are easier to feel in the mouth than to see on paper, and the merged vowels are exactly the ones you practised in Level 1.