Anchor: Two boys are ready to receive a ball at a tennis match.
Entailed: A pair of fans about to get a tennis ball.
Contradiction: Two boys are going to swim in the public pool.
Contradiction: Two girls are ready to receive a ball at a tennis match.
Contradiction: They're at a football game.
Contradiction: The two boys are tying their shoelaces.
Contradiction: An angry mob of children rioting in the streets.