Anchor: Oh; but he must do something.
Entailed: He has got to do something about something. 
Contradiction: He must like fruit, but definitely not vegetables. 
Contradiction: People are playing field hockey.
Contradiction: Adrin declared the giant was speaking. 
Contradiction: He knows he has no chance of ever being president.
Contradiction: It is not worth the time to learn it if it will not be used.