Policeman is the opposite of Criminal. Criminal is a type of Principal. 
Expensive is related to Bill. Bill is related to Cash. Cash is related to Reward. Reward is related to Compensation. 
Policeman <--Antonym--> Criminal --IsA--> Principal 
Expensive <--RelatedTo--> Bill <--RelatedTo--> Cash <--RelatedTo--> Reward <--RelatedTo--> Compensation 