rear beam

例句：

1. 1.The rear beam of the car is broken.
   汽车的后梁断了。
2. 2.The rear beam of the bridge supports the road surface.
   桥的后梁支撑着路面。
3. 3. The rear beam was reinforced to prevent further damage.
   后梁被加固以防止进一步损坏。