Verbs are made singular or plural by reference to their subject, so the subject must be properly identified.
DETERMINANTS OF SINGULAR AND PLURAL VERB FORMS
Making the correct choice between the singular and plural forms of a verb often presents a major grammar challenge in English. The choice requires answering two important questions:
1. What are the singular and plural forms of verbs? In many cases they are the same (e.g. in the past simple and past perfect tenses, and with “modal” verbs like will, can, should and must), but in many other cases a singular verb will need the ending –s and a plural will have no –s. This difference applies to the present simple and continuous tenses (knows, does not want, is going), the present perfect simple and continuous tenses (has known, has been helping), the past continuous tense (was standing), and the past tense of the verb BE (was).
2. Does the subject of the verb have a singular or a plural form? This question is important because the rule is that a singular subject must have a singular verb and a plural subject a plural verb.
Advanced learners of English tend to know point 1 (except with verbs in the “subjunctive” form – see 88. Exotic Grammar Structures 1, #6), but they can struggle with 2. This post therefore offers guidance with 2. It focuses on two separate problems – recognising the subject of a verb, and recognising whether that subject is singular or plural.
RECOGNISING THE SUBJECT OF A VERB
Subjects of verbs can be recognised from the following characteristics:
1. They are usually nouns or pronouns. Exceptions are adjectives with the before them, like the poor (see 6. Adjectives with No Noun 1: People-Naming), and verbs with –ing or to, as in Drinking alcohol can be harmful (see 70. Gerunds) and To see Paris is to see the world (119. BE Before a “to” Verb).
2. They usually appear before the verb. For example, the subject in Plants need water is plants, not water. An exception appears to exist with the verb there is/are, e.g. There are problems here. However, some grammarians say there is actually the subject here, even though the verb is plural like problems (see 161. Presenting Information with “There”).
3. They do not follow a preposition. In the sentence A pile of cash was on the table there are two nouns before the verb (pile and cash). The subject is not cash because it has the preposition of before it. More can be read about subjects and prepositions in the Guinlist post 84. Seven Things to Know about Prepositions.
4. They do not describe another noun directly after them. In the sentence Consumer demand affects prices, there are two nouns before the verb, but consumer cannot be the subject because it describes the following noun demand (for more details, see 38. Nouns Used Like Adjectives). In this example, identifying the correct subject noun ensures that the verb has the right form. Sometimes it can even ensure that the verb itself is right (see 132. Tricky Word Contrasts 4, item 1)
RECOGNISING WHETHER A SUBJECT IS SINGULAR OR PLURAL
“Singular” and “plural” can be understood in two ways: as forms of a word or as meanings. In the first case, a singular noun has no ending while a plural one has -s (or an equivalent); in the second case, a singular noun represents one of what the noun represents, while a plural one represents more than one. Usually it is the forms of singular and plural that determine the form of the verb, not the meanings. In most cases the forms correspond to the meanings, but sometimes they do not. For example, nouns in their singular form with a before them sometimes represent all of the possibilities in the world rather than just one (see 34. Relative Pronouns and Commas).
A quite serious problem is posed by “uncountable” nouns in English. They are nouns that cannot be given a plural form (see 110. Nouns without “the” or “a”). The problem is that sometimes their meaning seems to be plural, so that there can be a temptation whilst writing to give them a plural form – and hence to make the verb incorrectly plural as well – for example when referring to many pieces of baggage, paper, furniture or mail.
Some guidance on deciding whether a noun is countable or not is offered within this blog in posts with the title Noun Countability Clues. If you find you are using an uncountable noun as subject and you want to express a plural meaning, the only way to do so is to exchange the noun for a countable synonym (e.g. message for mail), or to use it after a countable division noun with of, as in pieces of paper, items of baggage and rounds of applause.
Another pitfall is collective nouns – nouns whose singular form represents a group of people, such as team, audience, government, crowd and committee. These singular forms are exceptional in allowing a choice between a singular and a plural verb. A singular verb emphasises the collectiveness of the group, while a plural one emphasises the individuality of the group members.
Mostly, however, when we think of a noun to write, it will already have the correct singular or plural form, and this form will indicate how to write the verb. Usually, we can expect an-s ending to need a plural verb and the absence of one to need a singular. The main danger is that -s has an opposite meaning on verbs, so that confusion can easily occur.
Unfortunately, –s is not a wholly reliable sign of a plural noun. Some singular nouns end in it, and some plural ones do not. Examples of singular nouns ending in -s are a means, a species, a series, an analysis, a circus and (a) business. Words ending in -ics (politics, mathematics, gymnastics etc), the illnesses measles and mumps, and the word news are also said by some books to be singular (uncountable) rather than plural because they typically take a singular verb.
The following are the main types of plural without -s:
1. Adjectives used like nouns, e.g. the poor, the unknowable (see 6. Adjectives with No Noun 1: People-Naming). These cannot have -s because it is only a feature of nouns.
2. Most pronouns (see 28. Pronoun Errors). Many plural pronouns have no ending at all. Of these, some are the same as their singular form (some, any, the relative pronouns who[m]/which/that, interrogative pronouns such as who?/whose?/what?), while others have no singular form at all (all, both, two, three etc.). Apart from these, I becomes we, this becomes these, that becomes those, much becomes many, and he/she/it become they.
3. Many nouns with an irregular plural form. Examples are people, (wo)men, children, cattle, oxen, sheep, fish, teeth, feet, phenomena, analyses (singular = analysis), media, larvae, alumni, offspring and aircraft. Some of these, like phenomena and larvae, have the plural ending of another language, from which they have been borrowed (see 90. The Greek Impact on English Vocabulary).
4. Nouns with a singular form but always a plural meaning: clergy, police, staff, vermin, folk, the youth (meaning “young people”).
5. Singular nouns connected by and, e.g. The President and his wife were present). It would be wrong to write was here.
Now here is an exercise through which you can test your command of singular and plural verbs.
EXERCISE: For each of the verbs in brackets in the following sentences, identify one word that agrees (as subject) with it, and then write the verb in its correct present simple tense form. Answers are given below.
1. The availability of computers in the workplace sometimes (MEAN) that employees (YIELD) to temptation to engage in non-work activities.
2. In a recent employers’ survey a wide variety of computer functions (HAVE) been identified as a potential distraction in offices that (NEED) to be addressed.
3. The survey (REVEAL) that the average employee on many occasions (EMAIL) friends from the office computer, that a small number (FOLLOW) sports events online or (MAKE) social arrangements, and that on some occasions even online shopping (TAKE) place.
4. The problem that employers (HAVE) (ARISE) because a worker’s visible actions easily (GIVE) the wrong impression.
5. Office workers who (STARE) intently at a computer screen while the mouse busily (CLICK) away (TEND) to make supervisors think genuine work (BE) being done when in fact drastic action urgently (NEED) to be taken.
ANSWERS: 1 =availability … MEANS, employees … YIELD; 2 = variety … HAS (but see below), that NEEDS; 3 = survey … REVEALS, employee … EMAILS, number … FOLLOW or FOLLOWS (see below), number … MAKE or MAKES, shopping … TAKES; 4 = employers … HAVE, problem … ARISES, actions … GIVE; 5 = who STARE, mouse … CLICKS, workers … TEND, work IS, action … NEEDS.
NOTE: The expressions a variety of and a number of are often taken as synonyms of many, so that the noun after of is thought of as the subject. Note also that subjects widely separated from their verbs are examples of interrupted structures (see 2. Reading Obstacles 1).