Joy is related to Peace. Peace is a synonym of Ease. Ease is the opposite of Difficulty. Difficulty is related to Level. 
Private is the opposite of General. General is related to Estimate. 
Joy <--RelatedTo--> Peace <--Synonym--> Ease <--Antonym--> Difficulty <--RelatedTo--> Level 
Private <--Antonym--> General <--RelatedTo--> Estimate 