I'm not 100% sure if this is what you mean but here are some examples:: Are you a football player? Do you play football? Are you a salesman? Do you sell products? So "Are you" is used in combination with a noun, and "Do you" is used in combination with a verb. If that's not what you mean, you might mean this: You are not really smart, are you? You do not know where my money is, do you? Hope this helps. Good luck.