Anchor: A group of boys in a desert playing with a ball.
Entailed: A group of boys playing in a desert.
Contradiction: A group of boys building sand castles in a desert.
Contradiction: The man has no tattos on his body.
Contradiction: There is a person who appears to be surfing.
Contradiction: Large is the only word suitable to describe the 8a level. 
Contradiction: You have a compelling argument.