When 2 words or 2 groups of words, usually joined by and or or, are the subject of the sentence, either the singular or plural verb form may be appropriate, depending on whether the words joined are singular or plural and on the connectors used.
Compound Subject Joined by and.
With and, a plural verb is usually correct.
The nurse and the physician are discussing my case.
A singular verb should be used if the 2 elements are thought of as a unit:
Dilation and curettage was suggested.
or refer to the same person or thing:
The first author and principal investigator takes responsibility for the data analysis.
Compound Subject Joined by or or nor.
With a compound subject joined by or or nor, the plural verb is correct if both elements are plural; if both elements are singular, the singular verb is correct. When one is singular and one is plural, the verb should agree with the noun closer to the verb.
Neither hospital staff nor family members were in the room.
Neither a false-positive result nor a false-negative result is definitive.
Neither the physicians nor the hospital was responsible for the loss.