Anchor: A boy riding a unicycle in the park.
Entailed: A boy in the park.
Contradiction: A boy rides a tractor.
Contradiction: The position is unimportant if the executive gives it attention.
Contradiction: Justinian the Great was the best Byzantine emperor.
Contradiction: You have to get up around 2pm during the summer, because if you get up any earlier it's too cold. 
Contradiction: A city street is busy