ferox

例句：

1. 1. The old iron door is covered in a thick layer of rust.
   这扇旧铁门上覆盖着厚厚的一层锈。
2. 2. The rusted metal was difficult to remove from the wall.
   生锈的金属难以从墙上移除。
3. 3. The rusty nails were holding the wooden plank together.
   生锈的钉子正在将木板固定在一起。