Enact is a synonym of Constitute. Constitute is a synonym of Establish. Establish is a synonym of Determine. Determine is a synonym of Regulate. 
Tax is a type of Charge. Charge is a synonym of Bill. Bill is a type of Proposal. 
Enact <--Synonym--> Constitute <--Synonym--> Establish <--Synonym--> Determine <--Synonym--> Regulate 
Tax --IsA--> Charge <--Synonym--> Bill --IsA--> Proposal 