Favorable is a synonym of Useful. Fire can be Useful. Fire is the opposite of Hire. Hire is a synonym of Rental. 
Recover is a synonym of Heal. Heal is related to Medicine. Vitamin is a type of Medicine. Vitamin is etymologically related to Vital. 
Favorable <--Synonym--> Useful <--HasProperty-- Fire <--Antonym--> Hire <--Synonym--> Rental 
Recover <--Synonym--> Heal <--RelatedTo--> Medicine <--IsA-- Vitamin --EtymologicallyRelatedTo--> Vital 