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to knead; to thicken into a paste (stirring over a flame)
to polish (a plan, etc.); to refine; to elaborate; to work out
to train; to drill; to exercise
to gloss (silk); to soften; to degum
to tan (leather)
to temper (steel)
to walk in procession; to parade; to march
腕を練るには実践の場が何よりも大切だ。
To hone skills, hands-on experience matters most.
技を練るために毎日欠かさず稽古を続けた。
I practiced without fail every day to refine my technique.
鉄を錬って刃を作る。
He forges iron into a blade.