The ending -야 돼요 is used to express necessity, obligation, or requirement. It means “must” or “have to”.
Structure:
Verb stem + -야 돼요 → “must / have to do something”
Examples:
Expressing a necessary action
학교에 가야 돼요. → “I have to go to school.”
빨리 먹어야 돼요. → “You must eat quickly.”
Stating a rule or requirement
숙제를 해야 돼요. → “I must do my homework.”
비밀번호를 입력해야 돼요. → “You have to enter the password.”
Giving advice or instructions
약을 먹어야 돼요. → “You must take your medicine.”
운동을 해야 돼요. → “You should exercise.”
The endings -야 돼요 and -야 해요 have exactly the same meaning