어야 하다

have to; should

Says the action or state is necessary — I have to get up, I need some luck, do I have to write my birthdate, you have to eat this in Taiwan. It is interchangeable in meaning with 어야 되다; the 하다 version reads slightly more formal and is the one you meet in writing and careful speech, though these clips also show it in playful chatter. The past form covers obligations that went unmet, as in the baseball game the speaker was supposed to watch and forgot.

Register: neutral, a touch more formal than 어야 되다