Complex sentence: Höhne was a pioneer ace; he was the first pilot to score a victory while flying the Fokker D.I During WWII he was a recipient of the Knight's Cross of the Iron Cross, which was awarded to recognise extreme battlefield bravery or successful military leadership.
Split into simpler sentences: Höhne was a pioneer ace; he was the first pilot to score a victory while flying the Fokker D.I During WWII he was a recipient of the Knight's Cross of the Iron Cross. The Knight's Cross of the Iron Cross was awarded to recognise extreme battlefield bravery or successful military leadership.