Complex sentence: Returning to Marsham's after he was discharged from the RAF in 1944, he supplemented his income by working as a journalist, writing for "The Star" during the 1948 Test series and penning three books with the assistance of a ghostwriter.
Split into simpler sentences: Returning to Marsham's after he was discharged from the RAF in 1944, he supplemented his income by working as a journalist. He wrote for "The Star" during the 1948 Test series and penned three books with the assistance of a ghostwriter.