rusty spot的用法和样例：
例句
- When he tried it the rusty metal did not budge, and he came away with red flecks covering his fingers.
他试了一试，这生锈的金属板一动也不动，他走到一旁，手指上满上剥落的红色的锈斑。 - Marble is a kind of natural material, have a lot of natural grain, form all sorts of different crackle that send form and tiny flaw or rusty spot in the surface.
大理石是一种天然材料，具有许多天然纹理，并在表面形成各种不同的发状裂纹和细小瑕疵或锈斑。
