Anchor: i don't know whether it is or not
Entailed: I don't know what's going on.
Contradiction: It definitely is not.
Contradiction: The woman is taking her cat to the vet.
Contradiction: For a description of prototyping and the spiral model, see Roger S. Pressman, Software A Practitioner's Approach, 3rd ed.
Contradiction: Two African american people are standing
Contradiction: There are more than one balloons.