Complex sentence: The 1st Battalion of the Suffolk Regiment was in the 8th Infantry Brigade, 3rd Infantry Division (United Kingdom) and served with the British Expeditionary Force in France where, with the rest of the BEF, it was evacuated from Dunkirk in 1940.
Split into simpler sentences: The 1st Battalion of the Suffolk Regiment was in the 8th Infantry Brigade, 3rd Infantry Division and served with the British Expeditionary Force in France. With the rest of the BEF, it was evacuated from Dunkirk in 1940.