Dream is related to Bad. Bad is related to Bone. Bone is related to Internal. Internal is the opposite of External. 
Efficiency is a type of Ratio. Economy is a type of Efficiency. Economy is related to Country. Country is related to Western. 
Dream <--RelatedTo--> Bad <--RelatedTo--> Bone <--RelatedTo--> Internal <--Antonym--> External 
Ratio <--IsA-- Efficiency <--IsA-- Economy <--RelatedTo--> Country <--RelatedTo--> Western 