plain concrete footing

例句：

1. 1. The engineer designeda plain concrete footing for the newbuilding.
   工程师为新建筑设计了一个平坦的混凝土基础。
2. 2. The construction crew used plainconcrete footings to support the weight ofthe heavy equipment.
   施工队伍使用平坦的混凝土基础来支撑重型设备的重力。
3. 3. Thefirm's headquarters is located on aplain concrete footing in downtown Manhattan.
   该公司总部坐落在曼哈顿市中心的一个平坦的混凝土基础上。