Gate is related to Doorway. Doorway is a synonym of Threshold. Threshold is related to Level. Level can be used for Construction. 
Bolt is a type of Bar. Bolt is related to Neck. Neck is a type of Opening. 
Gate <--RelatedTo--> Doorway <--Synonym--> Threshold <--RelatedTo--> Level --UsedFor--> Construction 
Bar <--IsA-- Bolt <--RelatedTo--> Neck --IsA--> Opening 