Complex sentence: Between March 9 and May 2 the Tonkin division had suffered heavily; many had died or were sick to disease, and in combat 774 had been killed, 283 wounded with another 303 missing or captured.
Split into simpler sentences: Between March 9 and May 2 the Tonkin division had suffered heavily; many had died or were invalided by disease. In combat 774 had been killed and 283 wounded with another 303 missing or captured.