Use "everyone" or "everybody" when talking about each and every person in a group. This is similar in meaning to the word "all"; however, this word is singular–it’s not plural.
subject = everyone or everybody
Everybody is here.
Does everyone have a seat on the bus?
This pronoun is singular even though it is used when talking to or about a group of people.
everyone / everybody
object = everyone or everybody
The teacher spoke to everybody.
Airport officials check everybody who goes through security.
whom = Anna
She spoke to everybody.
possessive adjective = everyone’s or everybody’s
Everyone’s seatbelt is on.
It’s everybody’s responsibility to remain seated until the ride is over.
Everyone’s safety belt is tight.
possessive pronoun = everyone’s or everybody’s
A: Whose park is this?
B: It’s everyone’s.
It’s everyone’s to enjoy.
reflexive pronoun = 0
When referring back to the subject, the grammatically best solution is to use "himself or herself." While this may sound awkward, it’s an acceptable alternative to "themselves" which is commonly used by Americans. (Everyone has to do this by themselves.)
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There are a few important things to consider when using these pronouns:
1. We often use the word "everyone" (or "everybody") when exaggerating or when we mean to say "a lot of people" or "many people." For example….
Millienium Park in Chicago is a popular destination for tourists. Everyone goes there. (Well, not everyone, but many people go there.)
Everyone had a good time at the party. (Actually, one or two people had a terrible time.)
Everybody loves this music. (No, not everyone, but many people do.)
2. In the present tense, ‘s is often used as a contraction for "is" and "has":
Everyone’s here. (Everyone is…)
Everybody’s having a good time. (Everybody is…)
Do you think everyone’s had enough to eat? (…everyone has had…)
Everybody’s got to go. (Everybody has got…)
3. When "everyone" is an antecedent, many people use "his or her" because there is no gender neutral singular pronoun in English. The alternative is to use a plural pronoun, which is what many Americans do:
Everyone has his or her own book. (correct)
Everyone has their own book. (incorrect, but many people find this usage acceptable.)
I couldn’t find my name on the list, but everyone else found theirs. (incorrect grammatically but still okay. To say "his or hers" sounds too correct.)