-아/어야 되다
Have to, Must
Use -아/어야 되다 to say you 'have to' or 'must' do something. It attaches to verb stems.
This pattern also has a main page: -아/어야 하다 (Must/should).
How It Works
This pattern is one of the most common ways to express obligation or necessity in Korean. It's equivalent to 'must' or 'have to' in English.
Conjugation Rules:
The conjugation depends on the last vowel of the verb stem.
- If the last vowel is ㅏ or ㅗ, you add -아야 되다.
- 가다 (to go) → 가 + 아야 되다 → 가야 되다
- 보다 (to see) → 보 + 아야 되다 → 봐야 되다 - If the last vowel is anything else (ㅓ, ㅜ, ㅣ, etc.), you add -어야 되다.
- 먹다 (to eat) → 먹 + 어야 되다 → 먹어야 되다
- 읽다 (to read) → 읽 + 어야 되다 → 읽어야 되다 - For 하다 verbs, it always becomes 해야 되다.
- 공부하다 (to study) → 공부해야 되다
- 운동하다 (to exercise) → 운동해야 되다
This pattern is very similar to -아/어야 하다, and in most situations, they are interchangeable. -아/어야 되다 can sometimes feel slightly softer, like a general rule or situational necessity, while -아/어야 하다 can imply a stronger sense of personal duty or resolve.
Examples (5)
- 내일 일찍 일어나야 돼요.
I have to wake up early tomorrow.
Word by Word: Tomorrow early have to wake up.
- 숙제를 다 해야 돼요.
I have to do all my homework.
Word by Word: Homework all have to do.
- 도서관에서 책을 빌리려면 학생증이 있어야 돼요.
To borrow books from the library, you must have a student ID.
Word by Word: In the library books to borrow if you intend student ID must exist.
- 비행기를 타기 전에 여권을 보여 줘야 돼요.
You have to show your passport before getting on the plane.
Here, the pattern is attached to the verb 주다 in the form of -아/어 주다 (to do for someone). 보여 주다 means 'to show'.
- 어제까지 보고서를 냈어야 됐어요.
I had to submit the report by yesterday.
This shows the past tense form, -았/었어야 되다.
Common Mistakes
Confusing obligation (-아/어야 되다) with permission (-아/어도 되다).
Different MeaningA: 지금 가도 돼요? (May I go now?) B: 네, 지금 가야 돼요. (Yes, you must go now.)BetterA: 지금 가도 돼요? (May I go now?) B: 네, 가도 돼요. (Yes, you may go.)-아/어야 되다 expresses obligation ('must'), while -아/어도 되다 expresses permission ('may'). Answering a question about permission with an obligation statement sounds unnatural and forceful, as if you are ordering the person to leave.
Learn This First
To express 'have to/must', you need necessity patterns and 되다.
Related Patterns
- -아/어야 하다Must/should
This pattern is nearly identical in meaning ('must', 'have to') and is often interchangeable with -아/어야 되다. -아/어야 하다 can sometimes imply a stronger, more active sense of duty, while -아/어야 되다 can feel more like a passive or external requirement.
- -지 않아도 되다Don't Have to, Not Necessary
This is the direct opposite, meaning 'you don't have to do something.' It expresses a lack of obligation. For example, '숙제를 해야 돼요' (You have to do homework) vs. '숙제를 하지 않아도 돼요' (You don't have to do homework).
- -(으)면 안 되다Must Not, Should Not
This pattern expresses prohibition ('must not', 'should not'). While -아/어야 되다 states what is necessary, -면 안 되다 states what is forbidden. They are logical counterparts.
- -아/어도 되다May, Be Allowed to
This pattern expresses permission ('may', 'it's okay to'). It's crucial to distinguish this from -아/어야 되다 (obligation), as they are often confused by learners due to their similar structure.
Learn Next
Patterns that build on this one.