Accident is etymologically related to Case. Case is related to Cover. Feather is a type of Cover. Feather is related to Wing. 
you are likely to find Drunk in/at/on Park. Park is the opposite of Street. you are likely to find Traffic in/at/on Street. 
Accident --EtymologicallyRelatedTo--> Case <--RelatedTo--> Cover <--IsA-- Feather <--RelatedTo--> Wing 
Drunk --AtLocation--> Park <--Antonym--> Street <--AtLocation-- Traffic 