Anchor: Students concentrate during class.
Entailed: Some people are being attentive.
Contradiction: One student is asleep in the room.
Contradiction: Users were hesitant to post on the controversial topic of marijuana, leading to very few people discussing the topic.
Contradiction: Two human beings are alive.
Contradiction: Czarek thought Miss Aldonka would have so much to say!
Contradiction: A man is trying to get out of a vehicle.