this site did a nice job with this discussion.
...there is one indefinite pronoun, none, that can be either singular or plural; it often doesn't matter whether you use a singular or a plural verb — unless something else in the sentence determines its number. (Writers generally think of none as meaning not any and will choose a plural verb, as in "None of the engines are working," but when something else makes us regard none as meaning not one, we want a singular verb, as in "None of the food is fresh.")
Edit: I like this one too:
- None of you claims responsibility for this incident?
- None of you claim responsibility for this incident?
- None of the students have done their homework. (In this last example, the word their precludes the use of the singular verb.
subject-verb agreement with ‘quantity’ determiners
The quantity determiners any, either, neither and none are sometimes used with a singular verb and sometimes used with a plural verb when they function as the subject of the clause.
Although the singular verb may be formally correct, in usage there is no strong preference for one or the other. So I think you may feel free to choose whichever you think best, depending, perhaps, on how strong you think the idea of plurality is.
Compare the following pairs and see which you prefer:
- I invited four policemen to my wedding but none was present.
- I invited four policemen to my wedding but none were present.
Student or Learner