Anchor: Further, if the mailbox rule were maintained, only one person will pick up an outgoing letter placed in the mailbox.
Entailed: The mailbox rule maintains that there will only be one person to pick an outgoing letter from a mailbox up. 
Contradiction: The mailbox rule says that any number of persons can pick up an outgoing letter from a mailbox. 
Contradiction: The city is equipped with just one subway line.
Contradiction: A high school marching band practices on the field at night.
Contradiction: I don't agree with you
Contradiction: Two women are drinking drinks