Reasonable is derived from Reason. Reasonable is etymologically related to Able. Enable is derived from Able. 
Government is related to Branch. you are likely to find Branch in/at/on Trunk. 
Reason <--DerivedFrom-- Reasonable --EtymologicallyRelatedTo--> Able <--DerivedFrom-- Enable 
Government <--RelatedTo--> Branch --AtLocation--> Trunk 