It's all in the mind.
みんな気のせいだ
It's all in the past.
((略式))すべて昔のことだ（忘れよう）
It's all on expenses.
それはすべて会社持ちだ
It's all one to me.
私にはどちらでも同じことです
It's all the same to me whether you pass the exam or not.
あなたが試験に合格しようがしまいが私にとっては同じことだ
It's an ill wind that blows nobody good.
((諺))だれにも利益をもたらさない風は吹かないもの；甲の損は乙の得
It's been a long time since I've seen you.
ずいぶん久しぶりだね
It's been a slice of life.
（一緒に過ごした時間は）楽しかった
It's been about a month since he got back from the U.S.
彼が合衆国から帰ってきて約１か月になる
It's been [((英))It's] three years since he went home.
彼が帰国してから３年になる
