Subject Verb Agreement

Basic Principle: Singular subjects need singular verbs; plural subjects need plural verbs. My brother is a nutritionist. My sisters are mathematicians.

1. The indefinite pronouns anyone, everyone, someone, no one, nobody are always singular and, therefore, require singular verbs.
2. Phrases such as together with, as well as, and along with are not the same as and. The phrase introduced by as well as or along with will modify the earlier word (mayor in this case), but it does not compound the subjects (as the word and would do).
3. The pronouns neither and either are singular and require singular verbs even though they seem to be referring, in a sense, to two things.
4. The conjunction or does not conjoin (as and does): when nor or or is used the subject closer to the verb determines the number of the verb. Whether the subject comes before or after the verb doesn't matter; the proximity determines the number.
5. The words there and here are never subjects.
6. Sometimes modifiers will get betwen a subject and its verb, but these modifiers must not confuse the agreement between the subject and its verb.
7. Words such as glasses, pants, pliers, and scissors are regarded as plural (and require plural verbs) unless they're preceded the phrase pair of (in which case the word pair becomes the subject).
8. Fractional expressions such as half of, a part of, a percentage of, a majority of are sometimes singular and sometimes plural, depending on the meaning. (The same is true, of course, when all, any, more, most and some act as subjects.)
9. If your sentence compounds a positive and a negative subject and one is plural, the other singular, the verb should agree with the positive subject.