📌 Expressing Obligation in Korean: -아/어야 되다/하다
📌 Must / Have to in Korean — -아/어야 되다 vs -아/어야 하다 (Beginner Friendly)
TOPIK 1–2 learners can master this pattern in one lesson.
▸ Table of Contents
1) What does it mean?
-아/어야 되다 / -아/어야 하다 → obligation / necessity
“I must / I have to / You should / You need to”
오늘 안에 끝내야 돼요. — I must finish it today.
2) How to form it
Step 1 — Choose -아/어야:
- ㅏ/ㅗ vowels → -아야 (가야, 봐야)
- Otherwise → -어야 (먹어야, 마셔야)
- 하다 verbs → -해야 (공부해야)
Step 2 — Add 되다 / 하다 endings:
가야 돼요 / 가야 해요 · 먹어야 돼요 / 먹어야 해요
3) Useful examples
약을 먹어야 해요. — I have to take medicine.
내일까지 숙제를 해야 돼요. — I must finish the homework by tomorrow.
오늘은 일찍 자야 돼요. — I should sleep early today.
운전면허가 있어야 해요. — You need a driver’s license.
한국에서는 신발을 벗어야 돼요. — You have to take off your shoes in Korea.
4) 되다 vs 하다 — difference?
-해야 돼요 → most common in spoken Korean
-해야 해요 → slightly more formal / written
👉 Both are correct. Choose one and be consistent.
5) Common mistakes
- 되요 ❌ → 돼요 ⭑ correct
- 금지 = -(으)면 안 돼요 (“must not”) not “안 + -어야 돼요”
- 과거 의무 = 았/었어야 했어요
6) Mini dialogue
A: 오늘 보고서 제출해야 돼요?
B: 네, 오후 세 시까지 내야 해요.
7) Your practice
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Tags: must in Korean, have to in Korean, beginner grammar Korean, study Korean, learn Korean