I know that this sentence is grammatically correct.Does Everyone have his or her dinner?
I know why they have used Does because Everyone is singular.
I know why they have used his/her because of Everyone is not plural.
Why did they use HAVE in this sentence? Since Everyone is singular so singular form i.e. has should be used, but they didn't. I know I'm in dark somewhere, please explain me the reason for it.
They used HAVE because DOES indicates the 3rd person singular, so HAVE must stand in infinitive.
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