grand duchy

例句：

1. 1. The grand duchy of Tuscany is a region with rich cultural heritage.
   托斯卡纳大公国是一个拥有丰富文化遗产的地区。
2. 2.The grand duchy of Savoy has been a center of art and culture for centuries.
   萨伏伊大公国几个世纪以来一直是艺术和文化的中心。
3. 3. The grand duchy of Milan is known for its beautiful architecture and historical landmarks.
   米兰大公国以其美丽的建筑和历史地标而闻名。