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to collect; to gather; to get together; to complete (a collection)
to arrange; to put in order; to prepare; to get ready
to make uniform; to make even; to match
散らばった机の上の本を揃えた。
I arranged the scattered books on the desk.
生徒全員の制服を揃えて購入した。
I purchased matching uniforms for all students.
部隊は歩調を揃えて行進した。
The troops marched in step.