you are likely to find Doorway in/at/on Room. Doorway is related to House. you are likely to find Computer in/at/on House. Computer is related to Bit. 
Profession is a type of Occupation. 
Room <--AtLocation-- Doorway <--RelatedTo--> House <--AtLocation-- Computer <--RelatedTo--> Bit 
Occupation <--IsA-- Profession 