the best response to any question. can be used on numerous occasions including insulting someone, an answer to a question you dont know the answer for, just for the hell of it or in concjuntion with a sentence. NB: it is important to find out about the status of the other person mother i.e. if something upsetting happened to her etc so no true insult is caused. P.S. the only people who WILL get really insulted then are silly or stupid and dont understand it is a joke and think you are really out to insult their family...
Percy: S'cuse me you've got something on your face.
Pat: Your mum's got something on her face.
Percy: okkkk... I havent got anyone to go to Prom with.
Pat: I'm going with your mum.
Percy: stop saying your mum!
Pat: your mum
Percy: your face!
Randomer: Percy dude that was harsh!
Percy: sorry Pat your actually really pretty, will you go to Prom with me?
Pat: I already told you i'm going with your mum!
Teacher: Percy stop talking in my lesson. Whats the answer to question 4?
Percy: Your mum?
Teacher: DETENTION! (note the inappropriate last use here where percy just doesnt know where to stop or how the phrase is used...note Pats master skills FYI she doesnt reall want to go to prom with percys mum duh!)