Sentence Correction (SC) | Re: According to the National Institutes of Health much of the sleep-depri

When you use person in plural form, it means about a very specific group, not the plural of person in general (and this should be "people").

I think good grammar books in countable plural noun will explain the difference. Otherwise, you can check the brief explanation from here:

https://dictionary.cambridge.org/gramma ... -or-people


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