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I'm sorry; my apologies; excuse me; pardon me
may I come in?
permission; leave; license
dismissal; discharge
not wanting; objecting to; being fed up with; wishing to avoid
ごめん、約束の時間に遅れてしまった。
Sorry, I was late for our appointment.
電話に出られなくてごめんなさい。
I apologize for not answering the phone.
ごめん、その日はもう予定が入っている。
Sorry, I already have plans that day.