小测验：选择正确的单词

1. Rust has already bitten into the enamel.
   铁锈已锈进搪瓷里面去了。
2. The rain has rusted the gate.
   雨水已使大门生锈。
3. There's a lot of old metal rusting in the garden.
   花园里有许多旧金属生锈了。
4. The iron pipe is scaly with rust.
   铁管子因为生锈一片片剥落了。
5. Rust had eaten out the gun barrel.
   枪筒已被锈蚀。

　1个名词解释