Approval is a type of Message. Approval is related to Prove. Approve is etymologically related to Prove. 
Bad is related to Trouble. you are likely to find Trouble in/at/on Street. Street is related to Gang. 
Message <--IsA-- Approval <--RelatedTo--> Prove <--EtymologicallyRelatedTo-- Approve 
Bad <--RelatedTo--> Trouble --AtLocation--> Street <--RelatedTo--> Gang 