Learn English – “is” vs “are” when followed by a number

One thing about plurals generally, is that we can sometimes think of them as a single unit.

For example, when we speak of "sports", are we speaking of "the several different activities, each of which is a sport", or are we speaking of "the single activity of engaging in sporting activities"?

The truth of the matter is that you can just as reasonable consider it either way; as a single concept that contains a plurality, or a plurality of concepts.

For the most part this is angels-on-pins stuff, but some plurals get referred to in a close-to-singular way often enough that people tend to think of them more as singular than as plural. And so sales isn't thought of as a collection of activities each of which is a sale, but as the name of an activity that businesses engage in. Sports is thought of as a thing*. Academic subjects are often referred to in the plural (mathematics, economics) but again each thought of as a thing.

And so when people go to use these words as an adjunct, they are thinking of them as singular, and while even always-plural words like trousers and scissors can become singular in trouser press and scissor blade, these words may remain in their plural form in sales manager, sports centre and mathematics textbook.

After all, when we speak and write we generally do not apply the rules rules of grammar in a fully concious way, but automatically. If we're thinking of a plural term as being singular, then we will use that plural term as if it is singular, even if the result does not fit logically with its actual plurality.

*There's some variance of use with sports with sport appearing in some cases as the name for the general activity and some papers having sport sections where some have sports sections, but that at least some usages favour the plural form here suffices to make it fit the pattern.

Some of the style guides that I have are categorical in claiming that the plural verb is correct in such constructions as:

One of the things that makes/make him great is he brings it every night.

Follet in Modern American Usage (p298) states:

These words (one of the [plural noun] who .. ) introduce the most widespread of all defiances of rudimentary grammar: the coupling of a plural subject with a singular verb.

Partridge in Usage and Abusage (p214) states:

The rule is that the formula, one of + plural noun, requires the ensuing verb to be plural.

The Right Word at the Right Time (p405) states:

The construction one of those who or one of the Xs that often presents the writer or speaker with a problem: does the verb that follows go into the singular or the plural? ... The answer is the plural: who or that refers not to one but to those or the Xs. (* See below)

Garner in Modern American Usage (p590) writes:

This construction requires a plural verb in the relative clause, not a singular one.

Other style guides offer a more nuanced approach. For example, the conclusion after a lengthy discussion of the construction in Merriam Webster's Dictionary of English Usage (p690) is:

So the choice of a singular or plural verb ... is a matter of notional agreement: is one or those (Xs) to be the master? .... There is abundant evidence that one has controlled number in modern English sentences from Shakespeare to James Kilpatrick, and there is likewise abundant evidence that those has controlled number in other sentences. Addison was not troubled by using both constructions. You need not be more diffident than Addison.

Peters in The Cambridge Guide to English Usage (p394) states:

For most writers the choice depends on whether you're thinking of a single case or a general principle. Usage commentators in the UK and the US have been inclined to say it should be the plural; and the Harper-Heritage usage panel voted heavily in its favor (78%). Yet Webster's English Usage (1989) found ample American evidence for the singular construction, and it's just as common as the plural in British data from the BNC. Writers using the singular take their cue from one, whereas plural users are responding to those [people] or the [things].

Finally, Steven Pinker, in his recent The Sense of Style (p250) writes:

For more than a thousand years the siren song of the singular one has overridden the syntactic demand of the plural those, and writer after writer has gone with the singular.

...

Usage guides today suggest that either the singular or plural is acceptable in this construction, depending on whether one or those looms larger in the writer's mind.

It is interesting that one of the sentences that The Right Word at the Right Time lists as ungrammatical is the following:

If you are one of those listeners who is alternately worried and puzzled by the state of modern English ... .

This sentence was written by pre-eminent British linguist Professor David Crystal.