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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
パン生地を丁寧に煉ってから焼く。
Knead the bread dough carefully before baking.
計画を十分に練ってから実行に移すべきだ。
You should refine the plan thoroughly before putting it into action.
文章を何度も練り直してようやく完成させた。
I reworked the text many times and finally completed it.