Anchor: From the shelter of the doorway he watched him go up the steps of a particularly evil-looking house and rap sharply, with a peculiar rhythm, on the door.
Entailed: He walked up the steps of an evil-looking house and knocked on the door. 
Contradiction: He was unable to knock on the door because he couldn't climb the steps.
Contradiction: Two dogs are on a bed.
Contradiction: Four men in a van, one giving the peace sign.
Contradiction: Two young boys watching their mom cook.
Contradiction: The weather is sub-tropical in the spring.