Park is related to Market. you are likely to find Seller in/at/on Market. Seller is related to Retailer. Retailer is derived from Retail. 
Toy is related to Bat. Bat is a synonym of Club. 
Park <--RelatedTo--> Market <--AtLocation-- Seller <--RelatedTo--> Retailer --DerivedFrom--> Retail 
Toy <--RelatedTo--> Bat <--Synonym--> Club 