Plane is related to Jet. Jet is a type of Fly. Fly is a type of Hit. Hit is related to Slap. 
Initiate is the opposite of Finish. Finish is related to Line. 
Plane <--RelatedTo--> Jet --IsA--> Fly --IsA--> Hit <--RelatedTo--> Slap 
Initiate <--Antonym--> Finish <--RelatedTo--> Line 