Iraqi is related to Oil. Oil is related to Pipe. Pipe is related to Mouth. you are likely to find Mouth in/at/on Human. 
Soap can be used for Bath. Bath can be used for Fill. Fill is the opposite of Drain. 
Iraqi <--RelatedTo--> Oil <--RelatedTo--> Pipe <--RelatedTo--> Mouth --AtLocation--> Human 
Soap --UsedFor--> Bath --UsedFor--> Fill <--Antonym--> Drain 