Complex sentence: General Denain served as Air Force Chief of Staff under Pierre Cot, replacing General Joseph Barès, from 10 March 1933 to 6 February 1934; he developed a strategic role for the Air Force with plans in 1933 for equipping it with 1,000 new planes.
Split into simpler sentences: General Denain served as Air Force Chief of Staff under Pierre Cot, replacing General Joseph Barès, from 10 March 1933 to 6 February 1934. Denain developed a strategic role for the Air Force with plans in 1933 for equipping it with 1,000 new planes.