Complex sentence: A major subordinate command of Forces Command, the U.S. Army Reserve Command (USARC), headquartered in Atlanta, Georgia, commands all U.S. Army Reserve units in the continental United States, except those assigned to Special Operations Command.
Split into simpler sentences: A major subordinate command of Forces Command is the United States Army Reserve Command (USARC), headquartered in Atlanta, Georgia. It commands all Army Reserve units in the continental United States, except those assigned to Special Operations Command.