Smoke is related to Power. Power is related to Brake. Brake is related to Part. Part is related to Lung. 
Corn is related to Origin. Cause is a type of Origin. 
Smoke <--RelatedTo--> Power <--RelatedTo--> Brake <--RelatedTo--> Part <--RelatedTo--> Lung 
Corn <--RelatedTo--> Origin <--IsA-- Cause 