Complex sentence: He sailed from San Diego, California, on March 11,1943, and arrived in New Caledonia later that month with the 1st Parachute Battalion, he left New Caledonia in September 1943.
Split into simpler sentences: He sailed from San Diego, California, on March 11,1943, and arrived in New Caledonia later that month. With the 1st Parachute Battalion, he left New Caledonia in September 1943.