have无非就两种用法一作实义动词一作助动词,当作实义动词时,即表示“有”时,用do来问.当作助动词时就用have问.
例：1.You have a car,don't you?当作实义动词时,即表示“有”时;
2.You have bought a car,haven't you?当作助动词时.