B2: Subject-Verb Agreement, Compound Subjects: Compound subjects combined with “and” take a plural verb form. Compound subjects combined with “or” “nor” or “but” must agree with the closest subject. The verb must agree with the subject that is nearest to the verb. See Writing for Success Section 2.2 pp. 58-59 or RULES 1 & 3 at the following: https://valenciacollege.edu/osceola/mainlab/documents/13RulesofSubject-VerbAgreement.pdf
Compound subjects with “and” = plural
Karen and Sharon shop at Costco.
The fifties diner and the pancake restaurant serve the same customer base.
Compound subjects with “or,” “nor,” and “but” agree with the nearest verb.
The street vendors or the fifties diner serve the night customers.
Neither Karen nor Sharon shops after dark.
Everyone but Sharon thinks pancake restaurant should be open for dinner.