roof beam

例句：

1. 1. Thebuilders were busy installing the new roofbeams.
   建筑工人忙于安装新的屋顶梁。
2. 2. The old house needed a lot ofrepairs, including replacing the roof beams.
   这所旧房子需要很多维修，包括更换屋顶梁。
3. 3. The engineer inspectedthe roof beams to ensure they werestrong enough for the structure.
   工程师检查了屋顶梁以确保它们足够坚固以支撑结构。