Tennis is a racket sport that can be played individually against
a single opponent (singles) or between two teams of two
players each (doubles). Each player uses a tennis
racket to hit a tennis ball over or around a net and into the
opponent's court. The object of the game is to hit the ball so
that the opponent is not able to return it. The player who is
unable to return the ball will not gain a point, while the
opposite player will.
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Tennis is played on a rectangular, flat surface. The court is 78 feet (23.77m) long, and 27 feet (8.2m) wide for singles matches and 36 ft (11m) for doubles matches.
The players or teams start on opposite sides of the net. One
player is the server, and the opposing player is the receiver.
Service alternates game by game between the two players or teams.
The server must hit a legal serve into the diagonally opposite box
to start the game. The server gets two serves. If the second
service, after a fault, is also a fault, the server double faults,
and the receiver wins the point. However, if the serve is in, a
rally commences in which the players alternate hitting the ball
across the net. A player or team cannot hit the ball twice in a
row. The ball must travel over or round the net into the other
players' court. The first player or team to fail to return the
ball loses the point.
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