Possibility is related to Case. Case is related to Work. Serve is a type of Work. 
Green is related to Sea. Sea is related to Island. Island is a type of Site. Cemetery is a type of Site. 
Possibility <--RelatedTo--> Case <--RelatedTo--> Work <--IsA-- Serve 
Green <--RelatedTo--> Sea <--RelatedTo--> Island --IsA--> Site <--IsA-- Cemetery 