crown of arch

例句：

1. 1.The crown of the arch is made of marble.
   拱顶由大理石制成。
2. 2. The dome of the cathedral is a marvel of architecture.
   大教堂的圆顶是建筑艺术的奇迹。
3. 3. The vault of the temple is lined with intricate carvings.
   寺庙的圆顶饰有复杂的雕刻。