beam lead bonder

例句：

1. 1. The beam of the roof is visible from here.
   从这里可以看到屋顶的梁。
2. 2. The beams are too weak to support the weight of the roof.
   这些梁太弱了，无法支撑屋顶的重量。
3. 3. The beams were made from wood and metal.
   这些梁是用木头和金属制成的。