Anchor: are they even are you are you in northern Virginia or are you in the District of Columbia
Entailed: Are you in the District of Columbia or are you in the northern part of Virginia?
Contradiction: I know where you are, don't worry.
Contradiction: The rule has been judged to be of no further interest.
Contradiction: It was a thick blade, like steel. 
Contradiction: A man is riding the bicycle.
Contradiction: The keys are for the two rooms.