Course is a type of Education. Course is related to College. College is related to Graduation. 
Should is related to Proper. Proper is a synonym of Total. Total is related to Age. Age is related to Being. 
Education <--IsA-- Course <--RelatedTo--> College <--RelatedTo--> Graduation 
Should <--RelatedTo--> Proper <--Synonym--> Total <--RelatedTo--> Age <--RelatedTo--> Being 