Complex sentence: Saarbrücken was created in 1909 by the merger of three towns, Saarbrücken, St. Johann and Malstatt-Burbach and used to be the industrial and transport centre of the Saar coal basin.
Split into simpler sentences: Saarbrücken was created in 1909 by the merger of three towns, Saarbrücken, St. Johann, and Malstatt-Burbach. It used to be the industrial and transport centre of the Saar coal basin.