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to use (a tool, method, etc.); to make use of; to put to use
to use (a person, animal, puppet, etc.); to employ; to handle; to manage; to manipulate
to use (time, money, etc.); to spend; to consume
to use (language); to speak
この道具を遣ってみて。
Try using this tool.
お金を大切に遣うべきだ。
You should use money carefully.
時間を上手に遣わないともったいない。
It's a waste if you don't use time well.