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to grapple with; to wrestle with; to engage in a bout; to be matched against
to tackle (e.g. a problem); to come to grips with; to work hard on
環境問題に積極的に取り組むべきだ。
We should actively address environmental issues.
新しいプロジェクトに取り組んでいる。
I am working on a new project.
彼は難しい課題に真剣に取り組んだ。
He seriously tackled the difficult task.