Complex sentence: The third version of the castle, which stands today, was constructed for Frederick William IV of Prussia between 1846 and 1867, under the direction of Friedrich August Stüler, who based his design on English Neo-Gothic style as well as the castles of the Loire Valley.
Split into simpler sentences: The third version of the castle, which stands today, was constructed for King Frederick William IV of Prussia between 1846 and 1867. The castle was built under the direction of architect Friedrich August Stüler, who based his design on English Gothic Revival architecture and the Châteaux of the Loire Valley.