Mr. Clinton and his 13-year-old son Tony are basketball fans. Last October 10th was Tony's birthday, so Mr. Clinton decided to drive him to New York, for the first game of the World Series. They had no ticket but hoped to buy a pair from scalpers . It was a two hours' ride. After they arrived, they walked in the street for two hours, carry ing a sign (牌子) that read, ' We need two tickets.' There were many scalpers around, but the cheapest ticket was $200. They were about to leave when suddenly a man stopped them. He took out two tickets and handed them to Mr. Clinton. 'How much do you want?' 'Just a present,' said the man. 'Enjoy the game.' Mr. Clinton wouldn't accept, so the man explained, 'I'm Jackson. Hans is my boss. He and his wife haven't missed a World Series in 18 years. But he is ill and can't watch the game this time. So he told me to give the two tickets to people who I thought would actually enjoy the game. A lot of people looked as if they might just take the tickets and sell them . Then I saw you and I followed you for a while. You seemed very disappointed. You made me think of my dad and me when I was a child. I dreamed of going to a World Series game with my father. But my dream never came true.' How do you suppose this made Mr. Clinton and his son feel? Here is what Mr. Clinton said: 'This is the most wonderful thing that ever happened to us. My boy and I must have turned to each other over 30 times and said, 'I can't believe this.' We still never forget Jackson and Hans.' 1. The underlined word scalpers in the first paragraph means ______.