Motor is related to Vehicle. Vehicle is related to Horn. Horn is related to Instrument. 
Combined is related to Mixture. Mixture is related to Stuff. Stuff is related to Buy. Buy is related to Register. 
Motor <--RelatedTo--> Vehicle <--RelatedTo--> Horn <--RelatedTo--> Instrument 
Combined <--RelatedTo--> Mixture <--RelatedTo--> Stuff <--RelatedTo--> Buy <--RelatedTo--> Register 