Need or needs

Nobody needs to know that...

Nobody need know that is also possible.

We usually say that words like anybody, anything, somebody, something, nobody, nothing, everybody, everything etc. are singular. So, it is needs

In the example I gave, 'need' is functioning as a modal. The form I gave, 'need' (with a final -s) is correct in all persons.

fivejedjonIn the example I gave, 'need' is functioning as a modal.

There are two English verbs that I know which can function as both modal and normal verb: need and dare.

He dare not rebuke his father.
How dare you come to school without your homework?

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