Football, game played on a rectangular (1) _______ by two opposing teams with an inflated leather ball that is roughly (2) _______ in shape. The object of the game is to score points by carrying the ball (3) _______ the opponent’s goal line or by (4) _______ the ball through the opponent’s goalposts. Football is (5) _______ a full-contact sport, meaning that play involves bodily contact by (6) _______ of checking, blocking, grabbing, and tackling. (7) _______ the rough physical nature of the game, playing football can cause injuries.
 This article (8) _______ on the game of American football, a distinct type of football that developed in (9) _______ in the 19^th century. It developed out of two other sports, soccer ((10) _______ known as association football) and rugby football, each of which remains a separate sport with its own specific set of rules. American football differs slightly in rules and field size from a style of football played mostly in Canada, called Canadian football. Other varieties of the game popular different parts of the world include Australian football and Gaelic football.