Constraint is a type of Restriction. Restriction is related to Law. Law is related to Rebel. Rebel is the opposite of Control. 
Course is related to Learning. Learning is related to Class. Class is related to Instance. 
Constraint --IsA--> Restriction <--RelatedTo--> Law <--RelatedTo--> Rebel <--Antonym--> Control 
Course <--RelatedTo--> Learning <--RelatedTo--> Class <--RelatedTo--> Instance 