you are likely to find Potato in/at/on Pot. you are likely to find Potato in/at/on Dirt. Dirt is related to Stone. 
Tragedy is the opposite of Comedy. Comedy is the opposite of Drama. 
Pot <--AtLocation-- Potato --AtLocation--> Dirt <--RelatedTo--> Stone 
Tragedy <--Antonym--> Comedy <--Antonym--> Drama 