Complex sentence: Although the 4th Panzer Division suffered heavy losses at Mokra on 1 September 1939 (800 men, between 100 and 160 AFVs), the remaining units of the XVI Panzer Corps did not take part in any major engagements.
Split into simpler sentences: Although the 4th Panzer Division suffered heavy losses at Mokra on 1 September 1939 (800 men, between 100 and 160 AFVs). Meanwhile the remaining units of the XVI Panzer Corps did not take part in any major engagements.