Anchor: Are they appropriate for the purpose of the case study?
Entailed: Someone is asking if something is important for a case study.
Contradiction: There is nothing associated with the case study.
Contradiction: It's better if, from an economic point of view, a postal service doesn't have a customer at all.
Contradiction: There are three men.
Contradiction: He did nothing for Hong Kong but make it weak and poverty stricken. 
Contradiction: The man is sitting on the ground.