Complex sentence: A British squadron attacked Saint-Florent in October, but was driven off by shore defences with heavy casualties, and the French were able to land significant reinforcements on the island in November and even conduct some local offensives against the Corsican forces.
Split into simpler sentences: A British squadron was sent to attack Saint-Florent in October, but was driven off by shore defences with heavy casualties. The French were then able to land significant reinforcements on the island in November and even conduct some local offensives against the Corsican forces.