sentences:  The magnitude of the defeat was so great that the mechanized corps parent headquarters of the tank divisions were either inactivated or destroyed by July 1941.Most of the tank divisions facing the Germans had met a similar fate by the end of 1941.The Soviets opted to organize more easily controlled tank brigades instead, eventually combining many of these into three-brigade tank corps in 1942, an organizational structure that served them until the end of the war.