Longtime is the opposite of New. New is related to Fashion. Fashion is related to Current. Current is related to Unit. 
Hand is related to Butterfly. Butterfly is related to Delicate. Delicate is a synonym of Weak. Weak is the opposite of Fast. 
Longtime <--Antonym--> New <--RelatedTo--> Fashion <--RelatedTo--> Current <--RelatedTo--> Unit 
Hand <--RelatedTo--> Butterfly <--RelatedTo--> Delicate <--Synonym--> Weak <--Antonym--> Fast 