Complex sentence: On 17 October he tried to break through to Gollnow with 5500 men to secure supplies from there, but the Russian general, William Fermor, stopped him at the bridge over the Ihna, in an artillery duel.
Split into simpler sentences: On 17 October he tried to break through to Gollnow with 5500 men to get supplies from there. But the Russian general, William Fermor, stopped him at the bridge over the Ihna, in an artillery duel.