Real is similar to Historical. Historical is the opposite of Expected. Expected is similar to Due. Due is related to Obligation. 
Combine is a type of Contribute. Contribute is a synonym of Afford. Afford is related to Range. Range is related to Son. 
Real <--SimilarTo--> Historical <--Antonym--> Expected <--SimilarTo--> Due <--RelatedTo--> Obligation 
Combine --IsA--> Contribute <--Synonym--> Afford <--RelatedTo--> Range <--RelatedTo--> Son 