raw copper

例句：

1. 1.The raw copper was melted down to make the new pipes.
   原始铜被熔化制成新的管道。
2. 2.The raw copper was used in the construction of the bridge.
   原始铜用于建造桥梁。
3. 3.The raw copper was refined into a shiny finish.
   原始铜被精炼成闪亮的表面。