Complex sentence: The morning drive time program began in August 1989 on CFNY-FM with Glassman as the sole host while Patterson was a sports anchor, although as the duo's comedic banter became an increasingly prominent feature of the show Patterson was eventually promoted to a full co-host.
Split into simpler sentences: The morning drive time program began in August 1989 on CFNY-FM with Glassman as the sole host and Patterson as sports anchor. As the comedic banter between the two became an increasingly prominent feature of the show, Patterson was eventually promoted to full co-host.