Complex sentence: In this brief period, Spaatz shot down three enemy planes and was awarded the Distinguished Service Cross (DSC); during the time he was promoted to the temporary rank of major on 17 June 1918.
Split into simpler sentences: In this brief period, Spaatz shot down three enemy planes and was awarded the Distinguished Service Cross (DSC); during the time he was. Spaatz was promoted to the temporary rank of major on 17 June 1918.