Complex sentence: The Slump of 1924 caused many British film studios to close, resulting in the passage of the Cinematograph Films Act 1927 to boost local production, requiring that cinemas show a certain percentage of British films.
Split into simpler sentences: The Slump of 1924 caused many British film studios to close. The Cinematograph Films Act 1927 was passed to boost local production, requiring that cinemas show a certain percentage of British films.