basal foot

例句：

1. 1.The base of the building is made of concrete.
   这座建筑的基础是用混凝土做的。
2. 2. The foundation of the new project is already laid.
   新项目的地基已经打好了。
3. 3. The pivot of the machine is located at the center.
   机器的支点位于中心。