bú kèqi
You're welcome
对不起
I'm sorry
对不起 is a fixed expression made of 对 (duì, 'toward') and 不起 (buqǐ, 'not up'), literally 'cannot face up to' someone. It's a set phrase, not built from parts you can rearrange.
抱歉
bàoqiàn
Sorry — More formal and polite.
对不起了
duìbuqǐle
Sorry (with emphasis) — More colloquial and emotional.
你迟到了!
Nǐ chídào le!
You're late!
对不起,我遇到了一些问题。
Duìbuqǐ, wǒ yùdào le yīxiē wèntí.
Sorry, I ran into some problems.
Appropriate
Avoid when
You can say 对不起 (duìbuqǐ). It is the standard way to apologize.
It is pronounced duìbuqǐ, with the neutral tone on the second syllable.
Use 对不起 when you have made a mistake or caused inconvenience, such as being late or accidentally bumping into someone.
Tomyo
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