During class, a teacher trying to teach good manners asks the students, one by one -
"Just a minute, I have to go piss."
The teacher replied "That would be rude and impolite!"
"What about you John, how would you say it?"
"I am sorry, but I really need to go to the bathroom, 'll be right back."
The teacher responded, "That's better, but it's still not very nice to say the word bathroom at the table."
"And you Peter, are you able to use your intelligence for once and show us your good manners?"
"I would say: Darling, may I please be excused for a moment, I have to shake hands with a very dear friend of mine, whom I hope you'll get to meet after supper."