あなたって、本当に

you really...

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phrase Rare #36,220
you really... A conversational way to emphasize a personal quality or behavior of the listener. Depending on context and intonation, it can express admiration, surprise, affection, or sarcasm. The って marks あなた as the topic.
JA: あなたって、本当に面白い人ね。
EN: You really are an interesting person.

あなたって、本当に変わった人ね

You really are a strange person.

あなたって、本当にやるつもりなの

Are you really planning to do it?

あなたって、本当に幸せそう

You really do look happy.

あなたって、本当に優しい人

You really are such a kind person.