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"Why does it not sell?" or "Why it does not sell?"

The first seems correct by gramatics but the second is suggested by my intuition.

marked as duplicate by FumbleFingers, StoneyB, Glorfindel, Chenmunka, JavaLatte Oct 21 '16 at 17:16

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  • What's important in an intterogative sentence(Question sentence) is its intonation. – user178049 Oct 21 '16 at 10:29
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    Fronted non-subjects, like the interrogative word "why" in your example, trigger subject-auxiliary inversion. So your first example is correct. – BillJ Oct 21 '16 at 11:52
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    Normally, one would say: Why doesn't it sell? – Lambie Oct 21 '16 at 16:05