Anchor: The current Clean Air Act has been enormously successful, but we can do better.
Entailed: The clean air act is successful but could be better
Contradiction: The clean air act is the best it could be 
Contradiction: three people are doing tile work
Contradiction: He might have had the idea it would be a safer thing in the long run.
Contradiction: A man is riding his skateboard on the boardwalk.
Contradiction: That is all you can do.