Roger Federer plays a game in which players use rackets to hit a ball or other object.
Roger Federer -LRB- born 8 August 1981 -RRB- is a Swiss professional tennis player .	tennis	tennis
Each player uses a tennis racket that is strung with cord to strike a hollow rubber ball covered with felt over or around a net and into the opponent 's court .	tennis racket	tennis racket	ball	Tennis ball	court	tennis court
