Cave is a type of Explore. Cave is related to Man. Man is related to Alien. Alien is a synonym of Foreign. 
Catalog is a type of Book. Book is related to Card. Card is related to Express. 
Explore <--IsA-- Cave <--RelatedTo--> Man <--RelatedTo--> Alien <--Synonym--> Foreign 
Catalog --IsA--> Book <--RelatedTo--> Card <--RelatedTo--> Express 