Anchor: That week, however, he didn't have the suture he needed to sew in the valves.
Entailed: He did not have his valves sewn that week.  
Contradiction: He had his valves sewn that week.  
Contradiction: Nevermind, we can talk for hours and hours because the store is closed.
Contradiction: A man working in the snow.
Contradiction: Verona has a large Greek theater.
Contradiction: I don't think anyone could call that food.