Complex sentence: Kaufman died of lung cancer in 1984, at the age of 35; however, because pranks and elaborate ruses were major elements of his career, persistent rumors have circulated insisting that Kaufman faked his own death as a grand hoax.
Split into simpler sentences: Kaufman died of lung cancer in 1984, at the age of 35. Because pranks and elaborate ruses were major elements of his career, persistent rumors have circulated insisting that Kaufman faked his own death as a grand hoax.