Anchor: How long can I keep saying, Oh, I didn't get it.
Entailed: I can't keep saying the same thing.
Contradiction: I can say that forever.
Contradiction: The sidewalk is empty.
Contradiction: There is a dog.
Contradiction: The area which surrounds Rome is extremely difficult to reach, even if you have lots of free time and your own transportation. 
Contradiction: I don't know for sure.