Does everyone know their name?

Zohar Levi1. Does everyone know their name?

Yes.

Zohar Levi2. Does everyone know what they are supposed to do?

Yes.

Zohar LeviWhere I treated everyone as singular while referring to plural.

They/their is not plural. These pronouns are used for the gender-neutral singular, since English is

Okay, and what if I do refer to a group of people in the two sentences, would it still be fine?

Zohar LeviOkay, and what if I do refer to a group of people in the two sentences, would it still be fine?

Please give an example sentence.

Hello class, ...
Dear assembly, ...
Boys and girls, ...

1. ... does everyone know their name?
2. ... does everyone know what they are supposed to do?

Zohar Levi1. ... does everyone know their name?2. ... does everyone know what they are supposed to do?

Those are exactly the same sentences you posted before. The answers have not changed since then.

To reiterate; you said my original sentences are fine, because they/their can refer to a singular as well. I wanted to confirm that even if I referred to a plural, it is still correct. As an example that you requested I added to the same sentences an initial addressing to a plural to clarify that everyone refers to a plural, e.g.:

"Boys and girls, does everyone know what they are supposed

Zohar LeviYeah, actually there's no ambiguity, I didn't need to clarify that everyone refers to a plural, this is usually the case.

'Everyone' is singular. It means 'every single one'. Although the message conveyed by everyone and all of you is the same, they are expressed in a different way grammatically.