red ocher的用法和樣例：
例句
- Because it reacts easily with oxygen in the air to produce crumbly red iron oxides.
因為它非常容易和空氣中的氧氣起反應，生成易碎的紅色氧化鐵。 - In other words, iron has a strong tendency to rust if exposed to air and damp, for iron and oxygen make rust, or red oxide of iron.
換言之，鐵如果接觸空氣和濕氣特別容易生銹，因為鐵與氧化合成銹或紅色的氧化鐵。
