贱金属

例句：

1. 1. The car was made of cheap base metal.
   这辆车是用廉价的贱金属做的。
2. 2. The construction workers used low-grade metal for the beams.
   建筑工人用低质量的贱金属做横梁。
3. 3. The new machine uses high-grade steel as its base metal.
   新机器用的是高质量的钢材作为基础金属。