Anchor: She did not pause to ascertain whether they were friends or foes.
Entailed: She didn't take the time to determine whether they were friends or enemies. 
Contradiction: She spent hours trying to decide whether they were friends or enemies. 
Contradiction: The valley has had major geographic changes over time.
Contradiction: I have participated in multiple Graphics Communications Association conferences. 
Contradiction: The island became independent of all external rule.
Contradiction: Skiiers stop at the top of the hill.