Snap is related to Finger. Finger is related to Put. Put is related to Lay. 
Sexy is a type of Book. Sexy is related to Blow. Blow is related to Air. 
Snap <--RelatedTo--> Finger <--RelatedTo--> Put <--RelatedTo--> Lay 
Book <--IsA-- Sexy <--RelatedTo--> Blow <--RelatedTo--> Air 