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to polish; to shine; to burnish; to scour; to scrub; to brush (teeth); to grind (e.g. a lens)
to refine (a skill, etc.); to improve; to hone; to polish (up); to cultivate (one's character)
毎朝歯を磨いてから出かける。
I brush my teeth every morning before going out.
腕を磨いて上手になろう。
Let's improve skills.
靴を磨くと気持ちも新しくなる。
Polishing shoes also refreshes my mood.