In my experience, the spelling checkers get confused by contractions. Your deduction, that not everybody's cup of tea means not to everyone's liking, is absolutely correct. There is a comprehensive article on the topic on grammar girl:
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What would be correct in this case and why? The indefinite pronoun 'everyone' is a singular pronoun. In fact, to catch someone's eye is an idiom, not eyes. the question is not about everyone being singular or plural.
Unless of course you’re a buddhist or a cat, in which case everyone has multiple lives and both would be correct, depending on context.
An example would be it flew over everyone's heads, or it flew over everyone's head. May i have everyone's attention,. The possessive form is everyone's (the form everyones' is incorrect).example: The indefinite pronoun 'everyone' is a singular pronoun that takes a singular verb.examples:
There are actually two issues concerning this topic: The expression commonly used in both the affirmative and negative. I have the following sentence: Should it be everyone's, everyones' or everyones?

Would the noun following everyone's be plural?
Joe got everyone's attention and started to speak. Everyone who is coming will receive a gift. Are the words everyone and everybody singular or plural? The possessive of everyone is everyone's, in the same way the possessive of everybody is everybody's.

