Wang Bin is a football fan. There is a football match between Chinese team and American team. He wants to watch it. He comes to the box office(售票处) and gives the clerk 10 yuan. The clerk -says, "please give me another 10 yuan. The price(价格) of a ticket is 20 yuan. "

"Why?" says Wang Bin, I just watch Chinese team. I don't want to watch the other team at all. Do you want me to buy a ticket for them? No, no, no... "