Anchor: A male practices BMX bike riding at and man made urban practice field with big lumps of dirt, water and a factory as a back drop.
Entailed: A man is riding a bike outdoors.
Contradiction: the man is at home sleeping
Contradiction: A man is riding a Segway through the woods.
Contradiction: Nobody is practicing.
Contradiction: A man rides a scooter downtown.
Contradiction: A woman rides her motorbike in a natural wooded setting.