Complex sentence: The years 2011 and 2012 were very successful for Sven Bender, he was an important player in Dortmund's midfield and helped the team win the national championship in both years as well as the German Cup in 2012.
Split into simpler sentences: The years 2011 and 2012 were very successful for Sven Bender. He was an important player in Dortmund's midfield and helped the team win the national championship in both years as well as the German Cup in 2012.