Sofa can be used for Seat. Seat is related to Pant. 
Defend is a type of Argue. Defend is a type of Prevent. Prevent is related to Avoid. Avoid is the opposite of Touch. 
Sofa --UsedFor--> Seat <--RelatedTo--> Pant 
Argue <--IsA-- Defend --IsA--> Prevent <--RelatedTo--> Avoid <--Antonym--> Touch 