Stiff is related to Board. Board is related to Material. 
Flash is related to Super. Super is related to Great. Great is related to Fine. Fine is related to Smooth. 
Stiff <--RelatedTo--> Board <--RelatedTo--> Material 
Flash <--RelatedTo--> Super <--RelatedTo--> Great <--RelatedTo--> Fine <--RelatedTo--> Smooth 