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Of the four main writing styles—commonly abbreviated as AP, APA, CMoS, and MLA—the Associated Press Stylebook and Briefing on Media Law (2017) and the 7th edition of the Publication Manual of the American Psychological Association (2019) recognize the formal use of singular “they” in their manuals.
The AP states: “They/them/their is acceptable in limited cases as a singular and/or gender-neutral pronoun, when alternative wording is overly awkward or clumsy” (p. 274).
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