Seminar is related to Class. Class is related to Rank. Rank is related to Major. 
Product is the opposite of Service. Service is related to Express. Express is related to Card. 
Seminar <--RelatedTo--> Class <--RelatedTo--> Rank <--RelatedTo--> Major 
Product <--Antonym--> Service <--RelatedTo--> Express <--RelatedTo--> Card 