Agency is a synonym of Representation. Representation is a type of Content. Content is related to Rice. Rice is a type of Pasta. 
Waste is the opposite of Gain. Gain is the opposite of Decrease. Decrease is a synonym of Sink. 
Agency <--Synonym--> Representation --IsA--> Content <--RelatedTo--> Rice --IsA--> Pasta 
Waste <--Antonym--> Gain <--Antonym--> Decrease <--Synonym--> Sink 