1. The ancient stone circles are believed to be earthfast structures used for rituals and ceremonies.
古老的石圈被认为是用于仪式和庆典的固定在地面上的建筑物。

2. The engineer inspected the earthfast foundation of the house to ensure its stability.
工程师检查了房屋的固定于地面的基础，以确保其稳定性。