Anchor: A guy surfing a wave successfully.
Entailed: A guy is surfing.
Contradiction: A guy tried to surf a wave but he fell off his board and drowned.
Contradiction: Those smoking side effects are exactly why I choose to smoke all the time.
Contradiction: I am a big fan of Jimmy Carter.
Contradiction: Everyone in the city is on the roof.
Contradiction: The boys both have the same immediate goal.