rust fungi

例句：

1. 1.The old car was covered in rust and needed to be cleaned.
   这辆旧车满是锈，需要清理。
2. 2. The rust on the metal surface is a sign of corrosion.
   金属表面的锈是腐蚀的标志。
3. 3.Rust can spread quickly if not treated properly.
   如果不妥善处理，锈会迅速蔓延。