"Rude" is an adjective that means not nice or impolite. We use this word for people who don’t consider how their behavior affects others (other people).
The saleswoman was rude to the customer, so the customer left the store without buying anything.
A student was being rude to the teacher, so the teacher told the student to leave the classroom.
It’s rude to interrupt a person who is talking.
A rude driver cut me off in traffic the other day, and then he gave me the finger!*
Why didn’t they call to say they would be late? That’s so rude!
The people who live above Bob play loud music past midnight every night. That’s rude.
Carla’s boss is rude to his employees.
Don’t be rude!
It’s rude to stick your tongue out at another person.
The word "rudely" is an adverb:
A student rudely interrupted the teacher.
My apology was rudely rejected by the person whose foot I stepped on.
