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relationship; relation; terms (good, friendly, etc.)
二人は幼なじみで気心の知れた間柄だ。
The two are childhood friends who know each other well.
上司と部下の間柄でも互いに敬意を持つべきだ。
Even in a boss-subordinate relationship, mutual respect is important.
二人は子供の頃からの親しい間柄だそうです。
Have a close relationship.