Anchor: The Portuguese also sailed down the west coast of Africa, going beyond Cape Bojador in 1434, a feat theretofore considered to be impossible.
Entailed: Before the Portuguese accomplished going past Cape Bojador, it was believed to be impossible to do so.
Contradiction: The Portuguese failed to sail down the west coast of Africa beyond Cape Bojador. 
Contradiction: Clutter the hall.
Contradiction: A surfer catching air, wearing only bottoms.
Contradiction: Three people are strolling through the park.
Contradiction: The cop knew this wasn't the way you came.