Complex sentence: The Oxfordshire and Buckinghamshire Light Infantry was a light infantry regiment of the British Army that existed from 1881 1958 when it was amalgamated with the Rifle Brigade and the King's Royal Rifle Corps to form the Royal Green Jackets, which later became The Rifles.
Split into simpler sentences: The Oxfordshire and Buckinghamshire Light Infantry was a light infantry regiment of the British Army that existed from 1881. In 1958 when it was amalgamated with the Rifle Brigade and the King's Royal Rifle Corps to form the Royal Green Jackets, which later became The Rifles.