Day is related to Week. Week is related to Quarter. Quarter is related to Metal. Metal is related to Category. 
Cheap is the opposite of Steep. Steep is related to Mountain. Mountain is related to Sky. 
Day <--RelatedTo--> Week <--RelatedTo--> Quarter <--RelatedTo--> Metal <--RelatedTo--> Category 
Cheap <--Antonym--> Steep <--RelatedTo--> Mountain <--RelatedTo--> Sky 