Have you ever met one? Someone who was all talk? Someone so full of herself that she thinks everything is about her or at least relates to her? Someone who, butts in to your conversations or worse, gives her opinion or advice, however unsolicited? Someone who when you ask her something always says 'Yeah I know that' or 'Sure, it's easy' and then when you try to ask her to elaborate, she falters and tries to change the subject? Someone who thinks she's better than you just because she speaks with an accent?
So, have you ever met one? Have you ever met a phony?
If you've ever met one, or just in case you meet one, here's an advice: Let them run their mouths dry and let them waste all their energy trying to impress you. Even if they don't come with a self-destruct button, they always manage to dig their own graves.
(As an add-on, if you want added entertainment, always play the innocent and ask them one question after another when they try to monopolize the conversation to highlight their proficiency on the subject matter.. watch them squirm as they begin to realize that you know better than they do and eventually shut up.)