Anchor: A muscular dog is walking on very short grass.
Entailed: A dog is walking.
Contradiction: A cat is walking.
Contradiction: On the coldest days it will be down near zero and the rest of the time it will be up around ninety.
Contradiction: The N-340 is lined with historic towns. 
Contradiction: A woman and two men are running in a marathon.
Contradiction: There is a man skateboarding.