Anchor: A narcotic taken with strychnine will delay the action of the poison for some hours." Poirot paused. 
Entailed: The presence of strychnine would pause the effect of the poison.
Contradiction: Strychnine would have no effect on the poison at all.
Contradiction: The pressure was eased when the mob left.
Contradiction: The skater is outside skating.
Contradiction: The man takes a nap on a tractor
Contradiction: Two men are performing.