steel timber

例句：

1. 1. The construction site is surrounded by towering steel structures.
   施工现场被高耸的钢铁结构包围。
2. 2. Steel is a strong and durable material that can be used for various purposes.
   钢铁是一种坚固耐用的材料，可以用于各种用途。
3. 3. Steel is often used in the manufacture of automobiles and other vehicles.
   钢铁常用于制造汽车和其他交通工具。