哥哥,don't have a pong-ping ball.为什么是don't have?

哥哥,don't have a pong-ping ball.为什么是don't have? I don't have a ping-pong ball.Does your brother have_____? -let`s play ping-pong.-_________!I don`t have a ball.应填sorry I don't have ping-pong balls后面的ball加s We don't have many picture.she doesn't have any ping-pong ha I don't have a soccer ball. ________you_______(have)a ping-pong ball? I have a ping-pong ball. Do _ have a ping-pong ball? We have a ping-pong ball. 为什么Does he have a ping-pong ball?为什么这个句子是Have的第三人称单数形式为什么不变H 同义句转换 I don't have a soceer ball,