everyone

[Suwei Wang]

Shall I say:

Everyone has their own concerns, don't they? or,
Everyone has their own concerns, doesn't he? or,
Everyone has their own concern, don't they?

Or else? Please advise.

[Casiopea]

Shall I say:

[1] Everyone has their own concerns, don't they? or,
[2] Everyone has their own concerns, doesn't he? or,
[3] Everyone has their own concern, don't they?

Or else? Please advise.

In [1], 'their' and 'they' are politically correct, but grammatically suspect.
In [2], 'he' is politically incorrect, but grammatically correct.

The rule of thumb is to try to use language that isn't suspect. For example,

They all, every one of them, have concerns, don't they?

In [1], [2] and [3], "their" represents a singular pronoun (i.e., combined she and he). Its referent is singular 'Everyone'. Again, it's politically correct, but grammatically suspect. That is, Standard English does not have--or at least not yet--a singular pronoun "their", but speaker do in fact use "their".

In [3], either 'concern' or 'concerns' is fine:

Every single one of the girls has her own concern.
=> Each girl has one concern.

Every single one of the girls has her own concerns.
=> Each girl has more than one concern.

[Suwei Wang]

Thank you very much for your quick reply. It's really helpful.

[Suwei Wang]

Sorry to trouble you again, but shall it be:

Every student needs to hand in his report tomorrow. or,
Every student needs to hand in their report tomorrow.

[Casiopea]

Try to use language that's not suspect; What about?

All students need to hand in their report tomorrow.