| 1 | The metal has corroded (away) because of rust. | |
| 2 | The one that I've got written down for you is it's the reverse of the rusting of iron, right? | |
| 3 | The same treatment is equally effective at removing the rust from corroded nuts and bolts. | |
| 4 | Standing between the two is an administrative machine corroded by apathy and corruption. | |
| 5 | Standing between the two is an administrative machine corroded by apathy and corruption. |