变锋利

例句：

1. 1.The chef uses a special knife to sharpen the blades of his knives.
   厨师使用一把特殊的刀来磨快他的刀。
2. 2.The carpenter sharpened the saw to make it more efficient.
   木匠把锯磨得更锋利，以便更高效地工作。
3. 3. The jeweler polished the diamond to make it shine brightly.
   珠宝商把钻石打磨得闪闪发光。