Complex sentence: The Mafeking Cadet Corps was a group of boy cadets formed by Lord Edward Cecil shortly before the 217 day Siege of Mafeking in South Africa during the Second Boer War in 1899-1900.
Split into simpler sentences: The Mafeking Cadet Corps was a group of boy cadets during the Siege of Mafeking in South Africa. The siege of Mafeking took place over 217 days during the Second Boer War in 1899-1900.