미안해요

mi-an-hae-yo · literally “I'm sorry”

Situation: Apologizing to your professor for submitting an assignment late

✕ What AI tells you

Translates 'I'm so sorry' as '정말 미안해요', because it's polite (ends in 요) and means sorry.

Why it fails: 미안하다 is the apology word for equals and juniors. To a professor, boss, customer or elder, even with 요 it can sound like you aren't taking the mistake seriously. 죄송하다 is the respectful form.

✓ What Koreans actually say

Apologize upward with 죄송합니다 / 죄송해요. Use 미안해요 / 미안해 with friends, partners and people younger than you.

  • 교수님, 늦게 제출해서 정말 죄송합니다.

    gyo-su-nim, neut-ge je-chul-hae-seo jeong-mal joe-song-ham-ni-da

    Formal apology to a professor or boss

  • 늦어서 죄송해요.

    neu-jeo-seo joe-song-hae-yo

    Polite but softer — a senior you're close to, a shop owner

  • 늦어서 미안해!

    neu-jeo-seo mi-an-hae

    Casual apology to a friend

Cultural nuance, in depth

Korean has two apology verbs, and the choice signals the relationship before the sentence ends. 죄송하다 contains 죄 (fault, offense) and expresses deeper humility, which is why it's also used by staff to customers and in public announcements. The reverse mistake matters too: saying 죄송합니다 to a close friend sounds distant, as if something serious has happened between you. 'Excuse me' to get past someone is a different expression entirely — 잠시만요 or 저기요, not an apology.