Railroad is etymologically related to Rail. Railroad is related to Old. Internet is made of Old. 
Boy is the opposite of Man. Man is related to Form. Form is related to Usual. 
Rail <--EtymologicallyRelatedTo-- Railroad <--RelatedTo--> Old <--MadeOf-- Internet 
Boy <--Antonym--> Man <--RelatedTo--> Form <--RelatedTo--> Usual 