Original: Critic Roger Ebert wrote of Keaton's "extraordinary period from 1920 to 1929, (when) he worked without interruption on a series of films that make him, arguably, the greatest actor-director in the history of the movies."
Simplified: Famous movie critic Roger Ebert wrote that Buster Keaton's "extraordinary period from 1920 to 1929, he worked without interruption on a series of films that make him, arguably, the greatest actor-director in the history of the movies."