Introduction is a type of Proposal. Introduction is the opposite of Conclusion. Conclusion is related to Theory. 
Unit is related to Home. Home is related to Personal. Personal is the opposite of Public. Public is similar to National. 
Proposal <--IsA-- Introduction <--Antonym--> Conclusion <--RelatedTo--> Theory 
Unit <--RelatedTo--> Home <--RelatedTo--> Personal <--Antonym--> Public <--SimilarTo--> National 