氧化还原作用

例句：

1. 1. Oxygen is an essential element for life on Earth.
   氧气是地球上生命所必需的元素。
2. 2. The chemical reaction involved in this process is known as oxidation.
   这个过程涉及的化学反应被称为氧化。
3. 3. The oxidation of iron occurs naturally in the soil.
   铁的自然氧化发生在土壤中。