Complex sentence: Due to the increased need for junior officers during the First World War, Feller's class was accelerated and graduated on November 1,1918 when Feller's was commissioned as a second lieutenant in the Coast Artillery Corps.
Split into simpler sentences: Due to the increased need for junior officers during the First World War, Feller's class was accelerated and graduated on November 1,1918. Upon graduation, Fellers was commissioned as a second lieutenant in the Coast Artillery Corps.