Eye is related to Big. Big is related to Hall. Hall is related to Capital. Capital is a type of City. 
Definition is a type of Explanation. Key is a type of Explanation. Key is related to Access. 
Eye <--RelatedTo--> Big <--RelatedTo--> Hall <--RelatedTo--> Capital --IsA--> City 
Definition --IsA--> Explanation <--IsA-- Key <--RelatedTo--> Access 