다고 나서다

step up and volunteer

A stated intention in -겠다고 plus 나서다 "come forward" means publicly taking something on rather than just mentioning it: 우크라이나는 아랍에미리트를 돕겠다고 나섰다, 대선 주자들이 일제히 근로소득세 부담을 줄이겠다고 나섰다. Every line here has that -겠다고 shape, and most of them are news or current-affairs commentary about a country, a company or a politician announcing they will act. Compare 하겠다고 하다, which is only saying you will; 나서다 adds actually putting yourself forward, sometimes with a hint that the speaker finds it presumptuous.

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