Number, in grammar, is a feature of language that indicates how many persons or objects are referred to. In English, the form of a noun shows whether the reference is to one person, place, object, or idea, or to more than one. The form that indicates only one is called the singular. The form that indicates more than one is called the plural. Some other languages have a singular form, indicating one; a dual form, indicating two; and a plural form, indicating more than two. The plurals of English nouns are formed in regular and irregular ways.
Regular plurals
are formed by adding –s or –es to the singular forms of the noun, as in cap, caps and church, churches. Compound nouns form plurals with the addition of –s or –es, but the placement varies. For example, the plural of brother-in-law is brothers-in-law. But the plural of grown-up is grown-ups. And in manservant, both parts take the plural form—menservants.
Irregular plurals
are not formed according to any established rule, as are regular plurals. The plurals of some nouns of Old English origin are formed by a vowel change, as in man, men and tooth, teeth. A small number of nouns still have the Old English plural ending –en—for example, ox, oxen and child, children.
About a dozen nouns that end in –f or –fe are changed to –ves in the plural, among them half, halves and wife, wives. But not all nouns that end in –f or –fe follow this pattern. For example, roof and chief form regular plurals—roofs and chiefs.
Some nouns, such as barracks, deer, and sheep, have the same form in both the singular and the plural. A few expressions use a singular form even though a plural is actually called for. These include two-inch nail, six-foot man, and two-gallon bucket.
Some nouns, including cowardice and brilliance, have no plural. They differ from such nouns as deer and sheep because two sheep is correct, but two cowardices is not. The plural of cowardice would usually be expressed by saying something like There are different kinds of cowardice.
Foreign plurals.
Words coming into English from foreign languages sometimes keep their foreign plurals. Such foreign plurals are mostly from Greek and Latin words. Some of these are phenomenon, phenomena; criterion, criteria; alumnus, alumni; alumna, alumnae; fungus, fungi; and thesis, theses. There is a strong tendency for such words to go into the regular English plural group. For example, at an earlier period the plural of stadium was the foreign form stadia. Now, however, stadiums is the plural form commonly used.
The spelling of plurals in English has many irregularities that are not reflected in speech. Singular nouns that end in –y, following a consonant, are changed to –ies in the plural—for example, lady, ladies; flurry, flurries; and candy, candies. For those ending in –y, preceded by a vowel, –s is added, as in alley, alleys and day, days. Some nouns that end in –o have –s added: silos and pianos. Others, for no special reason, have –es added: tomatoes and heroes. Several even have optional forms, such as zeroes or zeros and ghettoes or ghettos.
English pronouns
also have plurals, but the relationship is not so consistent as in nouns. We can be called the plural of I, and they the plural of he, she, and it. These is the plural of this, and those the plural of that.
English verbs
reflect number by agreeing with the subject. For example, the verb play occurs with a plural subject in the sentence The boys play baseball every day. The verb appears with a singular subject in The boy plays baseball every day.
