氧化铁

例句：

1. 1. The pigment in this paint is made from iron oxide.
   这种油漆中的颜料是由氧化铁制成的。
2. 2. The iron oxide layer on the surface of the soil helps to retain moisture.
   土壤表面的氧化铁层有助于保持水分。
3. 3. The process of converting iron ore into steel involves heating it to a high temperature and then reducing it withcarbon.
   将铁矿石转化为钢铁的过程包括将其加热至高温，然后使用碳将其还原。