Complex sentence: This position secured Gabes as a supply base but was easily outflanked to the west if a mobile force went around the Matamata Hills and Wadi Zigzaou put the French in front of a bottleneck, vulnerable to air and artillery fire.
Split into simpler sentences: This position secured Gabes as a supply base but was easily outflanked to the West if a mobile force went around the Matamata Hills. Moreover, Wadi Zigzaou put the French in front of a geographic chokepoint incredibly vulnerable to air and artillery fire.