Complex sentence: Nawab M. Ishak Khan designed the building himself, and the imposing project, upon 30 acres of land, was abated and consummated with the help of assistants who possessed considerable experience in building barracks for the British Army.
Split into simpler sentences: Nawab M. Ishak Khan designed the building himself, and the imposing project, upon 30 acres of land. It was designed with the help of assistants who possessed considerable experience in building barracks for the British Army.