Fishing is related to Pole. Pole is related to Rail. Rail is related to Support. Maintenance is a type of Support. 
Tighten is a type of Change. Changing is a form of Change. Changing is a synonym of Relief. Relief is a synonym of Comfort. 
Fishing <--RelatedTo--> Pole <--RelatedTo--> Rail <--RelatedTo--> Support <--IsA-- Maintenance 
Tighten --IsA--> Change <--FormOf-- Changing <--Synonym--> Relief <--Synonym--> Comfort 