Complex sentence: Train carriages for Sydney's expanding rail network were built and maintained within the building and included the Royal Carriages constructed specifically for the Governor General of Australia and visiting Royalty, the first electric carriage, and the first air-conditioned train in Australia.
Split into simpler sentences: Train carriages for Sydney's expanding rail network were built from scratch and maintained within the building. Carriages built there include the Royal Carriages constructed specifically for the Governor General and visiting Royalty, the first electric carriage, and the first air-conditioned train in Australia.