Assertion: american football | /r/HasProperty | played in the united states
Facets:
Source sentences:
text: American football, which uses 11-player teams, is the form played in the United States and the best known form of gridiron football worldwide, while Canadian football, featuring 12-player teams, predominates in Canada.
text: The CFL plays Canadian football, a form of gridiron football which is somewhat different from the more common American football played in the United States and the world.