Hospital is a type of Building. you are likely to find Elevator in/at/on Building. Car is part of Elevator. Car is related to Travel. 
Man is related to House. you are likely to find Air in/at/on House. 
Hospital --IsA--> Building <--AtLocation-- Elevator <--PartOf-- Car <--RelatedTo--> Travel 
Man <--RelatedTo--> House <--AtLocation-- Air 