sentences:  At the time of the German invasion, there were nine regular cavalry divisions and four mountain cavalry divisions in the Red Army.The rapid destruction of Soviet mechanized forces in the summer and autumn of 1941 resulted in a rapid expansion of cavalry units to provide the Red Army a mobile, if not armored, force.This expansion produced some 87 new cavalry divisions by early 1942, many of which were later disbanded as the Red Army rebuilt its tank and mechanized formations.