Complex sentence: That night several counterattacks were fought off and the following day, as a section of guns from the 2/1st Field Regiment arrived, the 17th Brigade went on the offensive and by 5 February the Japanese began withdrawing from the area.
Split into simpler sentences: That night several counterattacks were fought off and the following day, as a section of guns from the 2/1st Field Regiment arrived, the 17th Brigade went on the offensive. By 5 February the Japanese began withdrawing from the area.