is different; is another matter
だが連中は別だ
But they're different.
— ロシアン・ブラザー (1997)
恋愛と結婚は別だ。
Love and marriage are two different things.
彼は他の教師とは別だ。
He is different from the other teachers.
それなら話は別だよ。
In that case, it's a different story.
それとこれとは別だと思うよ。
I think those are two separate things.