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These days, more and more people begin to pay more attention to their health. They want to take up different kinds of sports to keep healthy. What sports should they do then?
Tennis
Thomas opened up a tennis room recently. To his surprise, there were much more people than he expected(预想) coming on the first day. Because no more room was available(可利用的), he had to rent(租借) another bigger room from his neighbour, but it still couldn't meet the need. "I am pleased to see so many people like playing tennis. It is a very good sport for health," said Thomas.
Football
Donna works in a bookstore. She often goes to play football in the middle school near the bookstore. "Although the students are having their summer holidays, to my surprise, the playground is crowded with people," said Donna.
Of course, there are some other sports that people can do to keep healthy. But it's certain(确定的) that people who often exercise can work better.