Complex sentence: In 1919 Damdinsüren began a rapprochement with the Mongolian revolutionaries, however, in the autumn of 1920 was arrested by Chinese occupation authorities and died in a prison in Niislel Khüree in January 1921.
Split into simpler sentences: In 1919 Damdinsüren began a rapprochement with the Mongolian revolutionaries. However, in the autumn of 1920 was arrested by Chinese occupation authorities and died in a prison in Niislel Khüree in January 1921.