Classroom have Floor. you are likely to find Door in/at/on Classroom. Booth have Door. Booth is related to Telephone. 
Stretch is related to Bend. Bend is a type of Section. Section is related to Department. 
Floor <--HasA-- Classroom <--AtLocation-- Door <--HasA-- Booth <--RelatedTo--> Telephone 
Stretch <--RelatedTo--> Bend --IsA--> Section <--RelatedTo--> Department 