R  module is isomorphic to a direct sum of copies of " R " as left ( resp .
Right ) " R " -module is isomorphic to a direct sum of copies of " R " as left ( resp .
Right ) " R " -module is isomorphic to a direct sum of copies of " R " as left ( resp .
أعد كتابة هذه الجملة: R  module is isomorphic to a direct sum of copies of " R " as left ( resp . خرج: