 Complete the following phrase:  By summer 1918, a million American soldiers, or doughboys as they were often called, of the American Expeditionary Force AEF were in Europe, serving on the Western Front under the command of General John Pershing, with 25,000 more arriving every week. The failure of the German Armys Spring Offensive exhausted its manpower reserves and they were unable to launch new offensives. The Imperial German Navy and home front then revolted and a new German government signed a conditional surrender, 