Anchor: Instead, the Romans built a gigantic ramp of rock and earth extending from the nearest adjacent mountain so they could simply march up to the level of the walls.
Entailed: The Romans got over the wall via a large ramp.  
Contradiction: The Romans used ladders to get over the wall.  
Contradiction: Two firefighters on bicycles are putting out a fire in a barn.
Contradiction: Mr. White said something agreeable.
Contradiction: They accidentally deleted the file containing the loan agreements. 
Contradiction: The girl is swinging.