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air; atmosphere
mood; situation
someone with no presence; someone who doesn't stand out at all
この部屋の空気が悪いね。
The air in this room is bad.
彼は場の空気を読まない人だ。
He's the type who can't read the room.
朝の新鮮な空気を吸おう。
Let's breathe the fresh morning air.