Page 557 - Practical English Usage 3ed - Michael Swan, Oxford

singular and plural (10): other points 532
2 co-ordinated subjects: A and 8, A or 8, A as well as 8, etc
When two singular subjects are joined by and, the verb is normally plural. Alice and Bob are going to be late.
But note that some phrases with and are treated like single ideas, and used with singular verbs (see 527.5).
Your toast and marmalade is on the table.
When two subjects are joined by as well as, together with or a similar expression, the verb is usually singular if the first subject is singular.
The Prime Minister, as weU as several Cabinet Ministers, believes in a tough financial policy.
The Managing Director, together with his heads ofdepartment, is preparing a new budget.
When two subjects are joined by or the verb is usually singular if the second subject is singular, and plural if it is plural. Compare:
There's no room - either two chairs or a table has got to be moved.
There's no room - either a table or two chairs have got to be moved. When two singular subjects are joined by neither . .. nor, the verb is normally singular in a formal style, but can be plural in an informal style.
Neither she nor her husband has arrived. (formal) Neither she nor her husband have arrived. (informal)
3 who and what
When who and what are used to ask for the subject of a clause, they most often have singular verbs, even if the question expects a plural answer.
Who is working tomorrow?~ Phil, Lucy and Shareena (are working tomorrow). (More natural than Who are working tomorrow?)
Who was at the party? (More natural than Who were at the party?)
What lives in those little holes?~Rabbits (do). (NOT Wh6t litJe ...)
When who and what are used to ask for the complement of a clause. they can have plural verbs.
Who are your closest friends? ~ (My closest friends are) Naomi and Bridget.
What are your politics?~ (My politics are) extreme left-wing. Relative what-clauses are normally the subject of a singular verb.
What she needs is friends. (More natural than What she needs are friends.) However, plural verbs are often used before longer plural complements, especially if what is a long way from the verb (see 529).
What we need most ofall are some really new ideas.
4 here's, there's and where's
In an informal style. here's. there's and where's are common with plural nouns. Here's your keys. There's some children at the door. Where's those books I lent you?
5 none, neither and either
When none, neither and either are followed by of+ plural noun/pronoun, they are normally used with singular verbs. Plural verbs are possible in an informal
style.
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