Complex sentence: Zwillman used this revenue to greatly expand his illegal operations into illegal gambling, prostitution, and labor union racketeering, as well as legitimate businesses including several prominant night clubs and restaurants and by the late 1920s Zwillman had an estimated income of $2,000,000 a year.
Split into simpler sentences: Zwillman used this revenue to greatly expand his operations in illegal gambling, prostitution, and labor racketeering, as well as legitimate businesses, including several prominent night clubs and restaurants. By the late 1920s Zwillman had an estimated income of $2,000,000 a year.