I am looking for an expression how to ask 'leave the classroom for several minutes to call somebody or to blow my nose, etc.' We usually use such an expression 'May I come in' when we would like to enter the room and I am looking for its antonym. Is it suitable to use 'go out/go off' for this purpose? I mean 'to leave the room for several minutes and then go back.'
May I be excused?
May I be excused? - May I leave this place, please?; May I leave to use the toilet?
Nature calls. May I be excused?
The student raised her hand and said, "Teacher, may I be excused?"