@phranck
English is a wacky language! (Makes sense, since it’s 3 or 4 languages smashed together and left to stew.)
Singular “they” is especially confusing because it’s under dispute; some people argue it’s incorrect. It’s similar to the alleged rule that one can’t end a sentence with a preposition — even though that’s (1) common and (2) a rule that one person made up because they thought English grammar should be more like Latin.
Good guidance on “they:”
https://style.mla.org/using-singular-they/
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