Pack is a type of Treat. Wrong is a type of Treat. Wrong is related to Fail. Fail is the opposite of Exam. 
Card can be used for Christmas. Card is related to Subject. 
Pack --IsA--> Treat <--IsA-- Wrong <--RelatedTo--> Fail <--Antonym--> Exam 
Christmas <--UsedFor-- Card <--RelatedTo--> Subject 