Union is related to Due. Due is related to Tax. Tax is related to Rape. Rape is a synonym of Violation. 
Car is related to Mechanic. Mechanic is similar to Mechanical. 
Union <--RelatedTo--> Due <--RelatedTo--> Tax <--RelatedTo--> Rape <--Synonym--> Violation 
Car <--RelatedTo--> Mechanic <--SimilarTo--> Mechanical 