Anchor: A boy on a bike is doing a stunt high in the air.
Entailed: A boy is riding a bike.
Contradiction: A girl is doing laundry
Contradiction: the women eats on her couch
Contradiction: People are getting married
Contradiction: I did not ask anyone to give an account of what happened.  
Contradiction: Unobligated balances expire at the end of the fiscal year.