Complex sentence: In 2012 and 2013, McGuinness co hosted one hour of the telethon with Christine Bleakley and Alesha Dixon was his co-presenter in 2014.
Split into simpler sentences: In 2012 and 2013, McGuinness co hosted one hour of the telethon with Christine Bleakley. However, Alesha Dixon was his co-presenter in 2014.