A、They are the leaders of these sports. B、They can cheer everyone up in the sport. C、They lead everyone to shout and cheer. D、Th

Americans learn sports as part of their education. They learn two or more ball games, such as football or basketball. At high school, they choose groups of boys or girls to make teams. They choose those who are best at that sport. These teams compete against teams from other schools. In many schools, students learn wrestling, running, tennis, golf and swimming. They have teams for some of these sports, too.
    The games between schools are often very exciting. Other students, the ones not on the team, love to watch them. They let everyone know this by shouting and cheering when their team plays well.
    There is a special club of girls and boys, mostly girls, who jump up and down and shout for their football team. They call themselves cheerleaders, because they lead everyone in shouts and cheers. They wear clothes of a special color—the color of their school’s team. The football players wear that color, too. Each school has a team color and a team name. Cheerleaders call out the team name in their cheers. They practice many hours to learn the special .jumping and cheering moves. Cheerleading is almost a sport itself.
    Every classroom has an American flag in it. From elementary to high school, students start each day by standing up and showing respect to the flag. They put their hands over their hearts and say "the Pledge of Allegiance". This is a promise to the country, which was written by people who came to the US over 200 years ago. By standing and showing respect to the flag, people think about the United States and its freedoms.
19. According to the speaker, who will be chosen to join the team?
20. Why do the girls and boys call themselves cheerleaders?
21. What can we learn about the cheerleaders in this passage?
22. What do the high school students do to start each day in America?