1.
our country, our nation
A formal expression meaning 'our country,' used in official speeches, government documents, academic writing, and news reporting to refer to Japan (or the speaker's own country). More formal than 日本.
In our country, the declining birthrate and aging population have become a serious problem.
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A formal, written expression. Used in government white papers, academic papers, news commentary, and official speeches. Not used in casual conversation, where 日本 or うち would be used instead.
Common patterns
我が is an archaic possessive form meaning "my" or "our." It survives in set expressions like 我が国, 我が家/我が家 (my home), and 我が社 (our company). In modern Japanese, 我が is not productive — it only appears in established compounds.