설명하다([seol-myeong-ha-da/explain]) means to explain or describe. In polite speech, say 설명해요([seol-myeong-hae-yo]).
설명했어요([seol-myeong-hae-sseo-yo/explained]) is the polite past form. Example: 방법을 설명했어요 (I explained the method).
설명해야 해요([seol-myeong-hae-ya hae-yo/have to explain]) means you must explain. Example: 지금 설명해야 해요 (I have to explain now).
설명하다([seol-myeong-ha-da/explain]) means "to explain". It is used when you make something clear in detail.
1. Daily: “방법을 설명해요 (bang-beo-beul seol-myeong-hae-yo)”
2. Past: 설명했어요([seol-myeong-hae-sseo-yo/explained]) explained.
3. Duty: 설명해야 해요([seol-myeong-hae-ya hae-yo/have to explain]) have to explain.
4. Warning: 설명하지 마세요([seol-myeong-ha-ji ma-se-yo/don't explain]) don't explain.
A: What do you explain?
B: 방법을 설명해요. B: bang-beo-beul seol-myeong-hae-yo.B: I explain the method.
A: 왜 설명해요? A: wae seol-myeong-hae-yo?A: Why do you explain?
B: 이해 못 해서 설명해요. B: i-hae mot hae-seo seol-myeong-hae-yo.B: I explain because they don't understand. - 설명하다([seol-myeong-ha-da/explain])
A: Did you explain yesterday?
B: 네, 설명했어요. B: ne, seol-myeong-hae-sseo-yo.B: Yes, I explained.
A: 뭘 설명했어요? A: mwol seol-myeong-hae-sseo-yo?A: What did you explain?
B: 계획을 설명했어요. B: gye-hoe-geul seol-myeong-hae-sseo-yo.B: I explained the plan. - 설명했어요([seol-myeong-hae-sseo-yo/explained])
A: When do you have to explain?
B: 지금 설명해야 해요. B: ji-geum seol-myeong-hae-ya hae-yo.B: I have to explain now.
A: 뭘 설명해야 해요? A: mwol seol-myeong-hae-ya hae-yo?A: What do you have to explain?
B: 보고서를 설명해야 해요. B: bo-go-seo-reul seol-myeong-hae-ya hae-yo.B: I have to explain the report. - 설명해야 해요([seol-myeong-hae-ya hae-yo/have to explain])
• 설명하다([seol-myeong-ha-da/explain]) explain
- 설명했어요([seol-myeong-hae-sseo-yo/explained]) explained
- 설명하고 싶어요([seol-myeong-ha-go si-peo-yo/want to explain]) want to explain
- 설명해야 해요([seol-myeong-hae-ya hae-yo/have to explain]) have to explain
- 설명하지 마세요([seol-myeong-ha-ji ma-se-yo/don't explain]) don't explain