1112: 'Everyone' can be Plural Dec 25, 2017
Words like 'everyone', 'anyone' and 'nobody' are all considered to be grammatically singular, but sometimes this is not semantically accurate. It is reasonable that 'anyone' etc are considered singular, given that the determiner alone tends to act as a singular (e.g. 'any dog', 'any chair' etc) because 'every' and 'any' and the rest all refer to one unit selected out of a whole group. In both meaning and grammar then, it is singular. In other constructions however, such as "everyone, children or adults, who gets lost or is in danger should know the Morse code for SOS" [1] (taken from a Dear Abby from 2000) uses the grammatical singular as is evidenced by the conjugated 'gets' and 'is' but clearly refers to two elements at once, which furthermore happen to be plural themselves. Likely, without the 'everyone', it would appear as "children or adults, who get[] lost or [are] in danger..." as otherwise this would sound odd. Often, people get used to hearing the same grammatical constructions without thinking of the meaning, but even if this is not grammatical necessarily, it is still understandable to a native speaker.
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