Expressing 'have to'

01

Forming the Structure

To create this form, you first conjugate the verb stem as if you were making the present tense (the 아/어/여 (a/ŏ/yŏ) form), but you attach 야 (ya) instead of 요 (yo).

• Stems ending in ㅗ (o) or ㅏ (a): Add 아야 (a·ya).
• Stems ending in other vowels: Add 어야 (ŏ·yaeo·yaŏ·yae·ya).
• Verbs ending in 하다 (ha·daha·daha·daha·ta): Change to 해야 (hæ·yahae·yahae·yahay·ya).

After forming this stem, you add either 하다 (ha·daha·daha·daha·ta) or 되다 (doe·dadoe·dadoe·dadoe·ta) and conjugate that final verb to match the politeness level of the conversation.

• 가다 → 가야 해요

  ga·da → ga·ya hæ·yoga·da → ga·ya hae·yoga·da → ga·ya hae·yoka·ta → ka·ya hay·yo

  to go → I have to go.

• 먹다 → 먹어야 해요

  mŏk·da → mŏ·gŏ·ya hæ·yomeok·da → meo·geo·ya hae·yomŏk·da → mŏ·gŏ·ya hae·yomek·ta → me·ke·ya hay·yo

  to eat → I have to eat.

• 청소하다 → 청소해야 해요

  chʰŏng·so·ha·da → chʰŏng·so·hæ·ya hæ·yocheong·so·ha·da → cheong·so·hae·ya hae·yoch'ŏng·so·ha·da → ch'ŏng·so·hae·ya hae·yocheng·so·ha·ta → cheng·so·hay·ya hay·yo

  to clean → I have to clean.

02

Choosing Between 하다 (ha·da) and 되다 (doe·da)

You will hear both 야 하다 (ya ha·daya ha·daya ha·daya ha·ta) and 야 되다 (ya doe·daya doe·daya doe·daya doe·ta). While they are often interchangeable, there is a slight difference in nuance and usage.

Using 하다 (ha·da) - To Do

야 하다 (ya ha·daya ha·daya ha·daya ha·ta) is the standard "textbook" form. It is slightly more formal and emphasizes the subject's active duty or obligation to perform the action. It is preferred in writing and formal speeches.

• 우리는 규칙을 지켜야 합니다.

  u·ri·nŭn gyu·chʰi·gŭl ji·kʰyŏ·ya ham·ni·da.u·ri·neun gyu·chi·geul ji·kyeo·ya ham·ni·da.u·ri·nŭn gyu·ch'i·gŭl ji·k'yŏ·ya ham·ni·da.u·li·nun kyu·chi·kul ci·khye·ya ham·ni·ta.

  We must follow the rules.

• 숙제를 해야 해요.

  suk·je·rŭl hæ·ya hæ·yo.suk·je·reul hae·ya hae·yo.suk·je·rŭl hae·ya hae·yo.suk·cey·lul hay·ya hay·yo.

  I have to do my homework.

Using 되다 (doe·da) - To Become/Work

야 되다 (ya doe·daya doe·daya doe·daya doe·ta) is very common in spoken, colloquial Korean. The verb 되다 (doe·dadoe·dadoe·dadoe·ta) means "to become" or "to work out." The literal nuance is "Only if I do this, will it work/be okay." It focuses more on the necessity of the situation rather than the person's will.

• 집에 가야 돼요.

  ji·be ga·ya dwæ·yo.ji·be ga·ya dwae·yo.ji·be ga·ya dwae·yo.ci·pey ka·ya tway·yo.

  I have to go home.

• 지금 자야 돼요.

  ji·gŭm ja·ya dwæ·yo.ji·geum ja·ya dwae·yo.ji·gŭm ja·ya dwae·yo.ci·kum ca·ya tway·yo.

  I need to sleep now.

03

The Casual Ending 야지 (ya·ji)

In casual speech (talking to friends or oneself), you can drop the final verb 하다 (ha·daha·daha·daha·ta) or 되다 (doe·dadoe·dadoe·dadoe·ta) entirely and simply end the sentence with 야지 (ya·jiya·jiya·jiya·ci).

This form is frequently used for self-talk when you are reminding yourself of a task, or showing determination. It cannot be used with the polite particle 요 (yo).

• 공부해야지.

  gong·bu·hæ·ya·ji.gong·bu·hae·ya·ji.gong·bu·hae·ya·ji.kong·pu·hay·ya·ci.

  I gotta study. (Self-talk)

• 너도 와야지!

  nŏ·do wa·ya·ji!neo·do wa·ya·ji!nŏ·do wa·ya·ji!ne·to wa·ya·ci!

  You have to come too! (Casual command)

• 늦었어, 빨리 가야지.

  nŭ·jŏ·ssŏ, bbal·li ga·ya·ji.neu·jeo·sseo, bbal·li ga·ya·ji.nŭ·jŏ·ssŏ, ppal·li ga·ya·ji.nu·ce·sse, ppal·li ka·ya·ci.

  It's late, I gotta go quickly.

04

Past Tense Obligation

To say you "had to" do something in the past, you conjugate the final auxiliary verb (하다 (ha·daha·daha·daha·ta) or 되다 (doe·dadoe·dadoe·dadoe·ta)) into the past tense.

• 어제 일해야 했어요.

  ŏ·je il·hæ·ya hæ·ssŏ·yo.eo·je il·hae·ya hae·sseo·yo.ŏ·je il·hae·ya hae·ssŏ·yo.e·cey il·hay·ya hay·sse·yo.

  I had to work yesterday.

• 병원을 가야 됐어요.

  byŏng·wŏ·nŭl ga·ya dwæ·ssŏ·yo.byeong·wŏ·neul ga·ya dwae·sseo·yo.byŏng·wŏ·nŭl ga·ya dwae·ssŏ·yo.pyeng·wŏ·nul ka·ya tway·sse·yo.

  I had to go to the hospital.