Complex sentence: His uncle, General P.P. Kumaramangalam was a veteran of the Second World War and a former Chief of Army Staff while his father Mohan Kumaramangalam was an important theorist and organiser of the undivided Communist Party of India.
Split into simpler sentences: His uncle, General P.P. Kumaramangalam was a veteran of the Second World War and a former Chief of Army Staff. Rangarajan's father Mohan Kumaramangalam was an important theorist and organiser of the undivided Communist Party of India.