Fate is the opposite of Free. Afraid is etymologically related to Free. 
Must is related to May. May is related to Summer. Summer is related to Salad. Salad is related to Meal. 
Fate <--Antonym--> Free <--EtymologicallyRelatedTo-- Afraid 
Must <--RelatedTo--> May <--RelatedTo--> Summer <--RelatedTo--> Salad <--RelatedTo--> Meal 