Essence is related to Core. Core is a type of Bar. Bar is related to Iron. Iron is a type of Implement. 
Present is related to Christmas. Christmas is related to Coal. Coal is related to Solid. Solid is the opposite of Soft. 
Essence <--RelatedTo--> Core --IsA--> Bar <--RelatedTo--> Iron --IsA--> Implement 
Present <--RelatedTo--> Christmas <--RelatedTo--> Coal <--RelatedTo--> Solid <--Antonym--> Soft 