timber sill beam

例句：

1. 1. Timber isa renewable resource that can be harvestedand reused.
   木材是一种可再生资源，可以采伐并重复使用。
2. 2. Theconstruction of the new bridge required a largeamount of timber.
   建造新桥需要大量的木材。
3. 3. Timber is often used to makefurniture and building materials.
   木材常用于制作家具和建筑材料。