Simplify the following text for a Grade 12 native English-speaking person.
Original: di was formed when the Deutsche Angestellten Gewerkschaft ( DAG ) ( German Salaried Employees ) merged with four unions of the Deutscher Gewerkschaftsbund ( DGB ) ( DPG , HBV , Ã -- TV , IG Medien ) .
Simplified: di was formed when the German Salaried Employees ' Union ( DAG ) merged with four unions of the German Confederation of Trade Unions ( DGB ) ( DPG , HBV , Ã -- TV , IG Medien ) .