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comfortably; peacefully; freely; with one's mind at ease; unrestrained; calmly; without worries; relaxed; carefree
(growing) quickly
子供をのびのび育てたい。
I want to raise my children freely
田舎でのびのび暮らしている。
I am living peacefully in the countryside
のびのびとした環境で働きたい。
I want to work in a relaxed environment