Maintenance is derived from Maintain. Maintain is the opposite of Abandon. Expose is a type of Abandon. 
Oven is related to Very. Very is related to Difficult. Difficult is related to Level. Level is related to Balanced. 
Maintenance --DerivedFrom--> Maintain <--Antonym--> Abandon <--IsA-- Expose 
Oven <--RelatedTo--> Very <--RelatedTo--> Difficult <--RelatedTo--> Level <--RelatedTo--> Balanced 