Agreement is an important concept in grammar and a source of many writing errors. Nouns must agree with their verbs, which means that a singular noun requires a singular verb, and a plural noun requires a plural verb.
The rabbit jumps up and down. (singular)
The rabbits jump up and down. (plural)
Remember that a noun ending in ‐s is often a plural, whereas a verb ending in ‐s is usually singular: four home runs (plural noun); he runs fast (singular verb).
Nouns with Latin or Greek endings and nouns that look plural but sometimes take singular verbs can cause agreement problems.
In the following example, criteria is plural. Use the plural form of the verb ( are).
The criteria for judging an entry are listed in the brochure.
Rights, which is a plural form, is treated as singular in the following example because human rights is a unit, a single issue of concern.
Human rights is an issue that affects everyone.
To emphasize the rights individually, use the plural verb.
Human rights are ignored in many countries.
In the next example, miles is the plural form, but fifty miles is used to identify a single unit of distance and therefore takes a singular verb.
Fifty miles is not such a long distance.
Statistics looks plural, and in many situations is treated as plural. In the first example below, statistics refers to a subject of study, so the singular verb is appropriate.
Statistics is a subject I want to avoid.
Statistics are being gathered to show that women are better drivers than men.
Among other frequently used nouns that can take either a singular or plural verb, depending on whether the emphasis is on a single unit or individual items, are number, majority, and minority.
The number of people coming is surprising.
A number of people are coming.
A number like five thousand is what he had in mind.
With number, use this rule. If number is preceded by the, always use the singular verb. If number is preceded by a, use the singular or plural, depending on whether you are describing a single unit or individual items.
With majority and minority, the key is to decide whether you want to emphasize individual people or things or the single unit.
The majority is opposed to the measure. (singular = single unit)
A minority of the younger people refuse to concede the point. (plural = individuals)