Complex sentence: The 1st Battalion, 12th Infantry Regiment, the Warrior Battalion, was formerly attached to the 3rd Brigade Combat Team of the the 4th Infantry division at Fort Carson.
Split into simpler sentences: The 1st Battalion, 12th Infantry Regiment is unit of the United States Army. Also known as the Warrior Battalion, it was formerly attached to the 3rd Brigade Combat Team of the US 4th Infantry Division at Fort Carson.