Complex sentence: The 1st RUR had the main road bridge over the river from Hamminkeln to Brunen as their objective, and the 12th Devons were to capture the town of Hamminkeln.
Split into simpler sentences: The 1st RUR had the main road bridge over the river from Hamminkeln to Brunen as their objective. While the 12th Devons were to capture the town of Hamminkeln.