Fall is a type of Be. Buy is a type of Be. Buy is related to Deal. Deal is a synonym of Mess. 
Test is related to Exam. Exam is the opposite of Fail. Fail is related to Rating. Rating is related to Parental. 
Fall --IsA--> Be <--IsA-- Buy <--RelatedTo--> Deal <--Synonym--> Mess 
Test <--RelatedTo--> Exam <--Antonym--> Fail <--RelatedTo--> Rating <--RelatedTo--> Parental 