Butt in 打断谈话，插嘴
I don’t like him. He kept on butting in with silly questions.
Butt out 走开！
This is none of your business, so butt out.
Cigarette butt 烟屁股，烟头
Cigarette butts were all over my house after the party.
A kick in the butt 教训
That speeding ticket was a kick in the butt for Dan. He really needs to get his driving under control.
Be the butt of sb's jokes
No one likes being the butt of a joke, but the best thing to do is just laugh with them.