Complex sentence: The Great Conservatory in the garden at Chatsworth was demolished as it needed ten men to run it, huge quantities of coal to heat it, and all the plants had died during the war when no coal had been available for non-essential purposes.
Split into simpler sentences: The Great Conservatory in the garden at Chatsworth was demolished as it needed ten men to run it and huge quantities of coal to heat it. All the plants had died during the war when no coal had been available for non-essential purposes.