Complex sentence: Boyne (2003), pp.220,221 Because the Luftwaffe's resources were needed for more critical duty in supporting the German army, the Luftwaffe became overstretched, and even victorious battles damaged the overall capability of Germany's air force due to attrition.
Split into simpler sentences: Boyne (2003), pp.220,221 Because the Luftwaffe's resources were needed for more critical duty in supporting the German army. The Luftwaffe became overstretched, and even victorious battles damaged the overall capability of Germany's air force due to attrition.