Complex sentence: The Second World War officially began two days later, 3 September 1939, and the brigade and division were called up for full-time war service and once again 125th Infantry Brigade was composed of three 1st Line battalions of the Lancashire Fusiliers.
Split into simpler sentences: The Second World War officially began two days later, on 3 September 1939, and the men of the brigade and division were called up for full-time war service. Once again the 125th Infantry Brigade was composed of three battalions of the Lancashire Fusiliers.