Complex sentence: On April 14,1965, SMOGists organized what they described as a "literary-political" meeting to commemorate the anniversary of Mayakovsky's death and to use the symbolism of the occasion to make a series of demands.
Split into simpler sentences: On April 14,1965, SMOGists organized what they described as a "literary-political" meeting to commemorate the anniversary of Mayakovsky's death. They used the symbolism of the occasion to make a series of demands.