Complex sentence: On November 28,1917, Shingarev was arrested at the home of Sofia Panina by Bolsheviks as a leader of the opposition and he was imprisoned in the Peter and Paul Fortress.
Split into simpler sentences: On November 28,1917, Shingarev was arrested at the home of Sofia Panina by Bolsheviks. As a leader of the opposition and he was imprisoned in the Peter and Paul Fortress.