Anchor: Three teens are standing next to each other in a classroom with a blackboard behind them.
Entailed: The teenagers are inside the classroom.
Contradiction: The children are outside playing.
Contradiction: The river has no cataracts, so travel up the river is easy.  
Contradiction: A man on a bench.
Contradiction: The Hackathletes are responsible for drafting quotations.
Contradiction: Nuclear War Averted just came in.