Complex sentence: After an intense and rapid training period, The units first mounted troops were deployed to the Border region by September of the same year the mounted troops began National Service in the conventional way, finishing basic training first before specialisation as mounted infantry.
Split into simpler sentences: After an intense and rapid training period, the units first mounted troops were deployed to the Border region. By September of the same year the mounted troops began National Service in the conventional way, finishing basic training first before specialisation as mounted infantry.