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のんき, 呑気, 暢気, 暖気
1. easy, easygoing, carefree, happy-go-lucky, optimistic, leisurely, careless, thoughtless
随和、悠闲、不经意
は
1. indicates sentence topic
2. indicates contrast with another option (stated or unstated)
3. adds emphasis
指示句子的主题;表示与另一选项(无论是否明确提及)形成对比;表示强调