girder grillage

例句：

1. 1. The bridge is made of steel girders and concrete slabs.
   这座桥由钢梁和混凝土板制成。
2. 2.The engineer used a steel girder to support the weight of the building.
   工程师用一根钢梁支撑着大楼的重量。
3. 3.The construction workers were busy installing the steel girders for the new bridge.
   建筑工人忙于安装新桥的钢梁。