Complex sentence: Its last assignment was with the 25th Bombardment Group at Alamogordo Army Air Field, New Mexico where it was inactivated on 20 June 1944.
Split into simpler sentences: Its last assignment was with the 25th Bombardment Group, based at Alamogordo Army Airfield, Alamogordo, New Mexico. It was inactivated on 20 June 1944.