Complex sentence: After scriptwriting on two productions, Powell entered into a partnership with American producer Jerry Jackson in 1931 to make "quota quickies", Powell began to direct hour-long films needed to satisfy a legal requirement that British cinemas screen a certain quota of British films.
Split into simpler sentences: After scriptwriting on two productions, Powell entered into a partnership with American producer Jerry Jackson in 1931 to make "quota quickies". Powell then began to direct hour-long films needed to satisfy a legal requirement that British cinemas screen a certain quota of British films.