这个磨刀石表面涂有金刚砂，可以轻松磨利刀具。

The sharpening stone is coated with ___carborundum to easily sharpen knives.

这块古董手表已经运行了50年，依然像碳化硅做的一样滴答作响。

This vintage watch has been working for 50 years, still ticking like it's made of ___carborundum.