Anchor: Strychnine is, in a certain sense, a cumulative poison, but it would be quite impossible for it to result in sudden death in this way. 
Entailed: Strychnine is a poison which needs a lot of time to affect somebody's health noticeabily.
Contradiction: Strychnine can under no circumstances cause death.
Contradiction: A woman passed her exam.
Contradiction: A female is cleaning
Contradiction: The cowboy is riding a bull.
Contradiction: A woman cuts cheese.