"你哪里不对劲" can be translated into English as "What's wrong with you?" or "Is there something off about you?"
The first translation, "What's wrong with you?", is a more common and straightforward expression in English, often used when someone notices unusual behavior or appears unwell.
The second translation, "Is there something off about you?", is a slightly more polite or nuanced way of asking the same question, implying that there might be something not quite right or out of the ordinary about the person.
Both translations convey the same basic meaning, but the choice between them may depend on the context and the relationship between the speakers.