Football is related to Guard. Guard is related to Defend. Defend is a type of Prevent. Prevent is the opposite of Let. 
Tea is related to British. British is related to Colony. Colony is related to Town. Town is related to District. 
Football <--RelatedTo--> Guard <--RelatedTo--> Defend --IsA--> Prevent <--Antonym--> Let 
Tea <--RelatedTo--> British <--RelatedTo--> Colony <--RelatedTo--> Town <--RelatedTo--> District 