In this talk I present a formal analysis of the English Negative Auxiliary Inversion (NAI) construction (Blanchette & Collins 2017). NAI constructions (e.g. ‘Didn’t many people come’) are string identical to yes/no questions, and are employed and interpreted as declaratives. They are found in many English varieties including Appalachian (Wolfram & Christian 1976), African American (Green 2002, 2014), and West Texas English (Foreman 1999). The formal analysis I present captures several syntactic and semantic properties of NAI, including (i) the absence of semantic ambiguity despite the presence of two scope-bearing elements, (ii) the impossibility of definite noun phrases in NAI subject position, and (iii) the parallel between NAI subjects and noun phrases that can be directly modified by negation (e.g. ‘not many people’). Extending beyond the formal analysis, I discuss how NAI constructions might inform our understanding of the role of standard language ideology (in the sense of Milroy 2001) in shaping synchronic properties as well as linguistic theories of natural language variation.