Complex sentence: Educated at Eton, Magdalene College, Oxford and Trinity College, Dublin, he entered the Army as a Cornet in the 18th Dragoons in 1774, rising to a Lieutenant the next year.
Split into simpler sentences: Educated at Eton, Magdalene College, Oxford and Trinity College, Dublin. He entered the Army as a Cornet in the 18th Dragoons in 1774, rising to a Lieutenant the next year.