for the mind.

　　You don't always have lots of __12__ to think when playing chess. There is a type of chess with short time limits. It's called speed chess. Each player gets ten minutes to __13__ for the whole game. Your clock runs during your __14__. You hit the time clock after your move. This stops your clock. It also __15__ the other player's clock. __16__ you run out of time, you lose.

　　Chess is not just for __17__. Computers have been playing chess since the 1970s. At first they did not play __18__. They made mistakes. As time went on they grew __19__. In 1997, a computer beat the best player in the world for the first time. It was a computer called Deep Blue. Deep Blue was __20__. It took up a whole room. By 2006 a cellphone could beat the best players in the world.

　　语篇解读：本文是说明文。文章介绍了国际象棋的规则、类型及发展。

　　1．A.around B．away

　　C．back D．here

　　解析：选A　根据下文中的"People have been playing it for over 500 years."可知，国际象棋的存在已经有很长一段时间了。故填around，在此意为"出现，可用"。

　　2．A.student B．player

　　C．winner D．trainer

　　解析：选B　根据文中的"Chess is a two­player game ... The other uses the black pieces."可知，国际象棋是两人对局的，一名"玩家(player)"使用白棋，另一名玩家使用黑棋。

　　3．A.changes B．drops

　　C．breaks D．moves

　　解析：选D　下文中的"The players take turns moving"是提示，每个棋都有特别的"移动(moves)"方式。

　　4．A.balls B．pieces

　　C．kings D．seats

　　解析：选B　根据语境及上文中的"One ... The other uses the black pieces."可知，玩家们轮流移动他们的"棋子(pieces)"。

　　5．A.loses B．finds

C．chooses D．passes