顶杆

例句：

1. 1. The roof ofthe house is supported by a woodenbeam.
   这所房子的屋顶是由一根木梁支撑的。
2. 2. The car'sengine is mounted on a steel beam.
   汽车引擎安装在一根钢梁上。
3. 3. The constructionworkers used metal beams to reinforce thefoundation.
   建筑工人使用金属梁加固地基。