Complex sentence: Late in 1903 Preobrazhensky joined the Bolshevik faction of the RSDLP, carrying out underground Party work in Orel, Bryansk and Moscow, taking part in the 1905 uprising in the Presnensky District of Moscow.
Split into simpler sentences: Late in 1903 Preobrazhensky joined the Bolshevik faction of the RSDLP, carrying out underground Party work in Orel, Bryansk and Moscow. He took part in the 1905 uprising in the Presnensky District of Moscow.