Complex sentence: Michael Ryan Pritchard (born May 4,1972), known professionally as Mike Dirnt, is an American musician best known for being the co-founder, bass guitarist, backing and occasional lead vocalist of the American punk rock band Green Day.
Split into simpler sentences: Michael Ryan Pritchard (born May 4,1972), known professionally as Mike Dirnt, is an American musician. He is best known for being the co-founder, bassist, backing vocalist and occasional lead vocalist for American punk rock band Green Day.