약속하다([yak-sok-ha-da/promise]) means to give your word and make a commitment. In polite speech, say 약속해요([yak-sok-hae-yo]) or 약속드려요.
약속했어요([yak-sok-hae-sseo-yo/promised]) is the polite past form. Example: 친구랑 약속했어요 (I promised my friend / I made an appointment with my friend).
약속해야 해요([yak-sok-hae-ya hae-yo/have to promise]) means you must give your word. Example: 꼭 지킬 수 있는 것만 약속해야 해요 (You have to promise only what you can keep).
약속하다([yak-sok-ha-da/promise]) means "to promise". To give your word, make a vow, make an appointment.
1. Daily: “약속해요? (yak-sok-hae-yo)” Do you promise / make an appointment?
2. Past: 약속했어요([yak-sok-hae-sseo-yo/promised]) promised / made an appointment.
3. Duty: 약속해야 해요([yak-sok-hae-ya hae-yo/have to promise]) have to promise.
4. Warning: 약속하지 마세요([yak-sok-ha-ji ma-se-yo/don't promise]) don't promise.
A: Do you promise / make an appointment with your friend?
B: 네, 내일 7시에 약속해요. B: ne, nae-il il-gop-si-e yak-sok-hae-yo.B: Yes, I promise / have an appointment tomorrow at 7.
A: 어디서 약속해요? A: eo-di-seo yak-sok-hae-yo?A: Where do you promise to meet?
B: 공장 앞에서 약속해요. B: gong-jang a-pe-seo yak-sok-hae-yo.B: We promised to meet in front of the factory. - 약속하다([yak-sok-ha-da/promise])
A: Did you promise / make an appointment with the boss yesterday?
B: 네, 연장 근무 약속했어요. B: ne, yeon-jang geun-mu yak-sok-hae-sseo-yo.B: Yes, I promised overtime work.
A: 언제까지 약속했어요? A: eon-je-kka-ji yak-sok-hae-sseo-yo?A: Until when did you promise?
B: 오늘까지 끝내기로 약속했어요. B: o-neul-kka-ji kkeut-nae-gi-ro yak-sok-hae-sseo-yo.B: I promised to finish by today. - 약속했어요([yak-sok-hae-sseo-yo/promised])
A: Until when do you have to promise to pay back?
B: 다음 달까지 갚기로 약속해야 해요. B: da-eum dal-kka-ji gap-gi-ro yak-sok-hae-ya hae-yo.B: I have to promise to pay back by next month.
A: 꼭 지켜야 해요? A: kkok ji-kyeo-ya hae-yo?A: Do you have to keep it for sure?
B: 네, 약속은 꼭 지켜야 해요. B: ne, yak-so-geun kkok ji-kyeo-ya hae-yo.B: Yes, you must keep a promise. - 약속해야 해요([yak-sok-hae-ya hae-yo/have to promise])
• 약속하다([yak-sok-ha-da/promise]) promise / make appointment
- 약속했어요([yak-sok-hae-sseo-yo/promised]) promised
- 약속하고 싶어요([yak-sok-ha-go si-peo-yo/want to promise]) want to promise
- 약속해야 해요([yak-sok-hae-ya hae-yo/have to promise]) have to promise
- 약속하지 마세요([yak-sok-ha-ji ma-se-yo/don't promise]) don't promise