Beginning of Essay
The playing field is 120-yd (110 m) long and 53.3-yd (48.8 m) wide. At each end of the 100-yd main body of the playing field, white lines called goal lines mark off the entrances to the end zones. Each team defends one end zone and must carry or pass the ball into ....

Middle of Essay
.... officials. Two teams of 11 players play football. Each team tries to move the ball down the field to score in the end zone defended by its opponent. The team in possession of the ball is called the offense, and the team defending is called the defense. Players involved in kicking situations are known as the special teams. The 11 players of the offensive team are divided into 7 linemen, who play on the line of scrimmage (an imaginary line designating the position of the ball) and a backfield of 4 players, called backs. The linemen are the center, the left and right guards, the left and right tackles, the tight end, and the split end. The back who dir ....