Complex sentence: The winning teams from each of the 19 groups in the Third Division, plus many number-two teams, were promoted to the Second Division (this was possible because of an enlargement of the Second Division from 6 to 8 groups).
Split into simpler sentences: The winning teams from each of the 19 groups in the 3. Divisjon (this was possible because of an enlargement of the 2. Divisjon from 6 to 8 groups).