Complex sentence: Mabel Normand (November 9,1892--February 23,1930) was an American silent film comedienne and actress, a popular star of Mack Sennett's Keystone Studios and noted as one of the film industry's first female screenwriters, producers and directors.
Split into simpler sentences: Mabel Normand (November 9,1892--February 23,1930) was an American silent film comedienne and actress. She was a popular star of Mack Sennett's Keystone Studios and is noted as one of the film industry's first female screenwriters, producers and directors.