Subject-Verb Agreement

Understanding How to Make Verbs and Subjects Agree in Number

Illustration of subject verb agreement
Singular subject takes a singular verb, and a plural subject takes a plural verb.

Subject-Verb Agreement is a fancy term for an idea that seems simple enough: the subject and the verb must walk together—meaning a singular subject takes a singular verb, and a plural subject takes a plural verb.

But the problem is, not all subjects clearly proclaim themselves to be singular or plural, and in many cases the plain grammatical form of the subject conflicts with our sense of the intended meaning.

For this reason grammarians have introduced the idea of s–endings, used in determining the condition of the subject and thus supplying the appropriate verb.

To adhere to the rules of subject-verb agreement, you must understand the concept of s–endings—for the rules guiding subject-verb agreement are all based on the use of S-endings.

There must be agreement between subject and verb in a sentence:

  • The pen writes.
    [Correct! subject is singular, verb also is singular]
  • The pens write.
    [Correct! subject is plural, verb also is plural]
Important Hint!  

Do not get confused between singular and plural verbs, because not all words ending in –s are plural. The –s has several other uses, depending on the kind of word it’s being tagged to. In the examples above, many learners might think ‘writes’ as a plural verb and ‘write’ as a singular verb.

Plural verbs forms are just opposite in the way nouns take their plural forms. Nouns are naturally made plural by adding ‘–s’ or ‘–es’ in singular noun. On the other hand, if you add ‘–s’ or ‘–es’ in a verb it becomes singular. As it is in the following:

Noun + s/es = PluralVerb + s/es = Singular
    Singular Noun
    ball, bench, book, utensil
    Singular Verb
    kicks, runs, sings, wanders
    Plural Nouns
    balls, benches, books, utensils
    Plural Verbs
    kick, run, sing, wander

Types of S–Endings

A.  The Natural S Several words in English have an S as their final letter. Meanwhile, these S’s are not endings. They only make part of the basic spelling of the word. For example, kiss, bus, miss, Paris, etc., all end in s the way other words may end in t or n or r, etc.

B.  The Noun S This is the common Plural S. By adding an S to the end of a singular noun, the noun becomes plural:

SingularPlural (+s)

By adding an –s ending, we now increase our object from one to more than one.

Sometimes a noun already ends in a Natural S. In such a case, we add an –es ending to make it plural, as follows:

SingularPlural (+es)

Other Uses of –es

An –es is used if a noun ends in ch, sh, x, or z:

SingularPlural (+es)

Likewise, nouns that ends in letter –y form plurals in one of two ways:

1.   If the letter before the –y is a consonant, the plural is formed by changing –y to I, then adding –es:

SingularPlural (–y + ies)

2.   When the letter before the –y is a vowel; an s is added.

SingularPlural (+s)

Note also that some nouns ending with letter fe or fe become plural by altering the f to v before adding –es:

SingularPlural (f › v + es)

However, some become plural by addition of an –s:

SingularPlural (+ s)

There are also nouns with an –o ending. These group of nouns form their plural by adding an –s:

SingularPlural (+ s)

Similarly, other nouns that end in –o take an –es to become plural:

SingularPlural (+ es)

3.  The Possessive S (’s or s’) — This form of S– ending is typically attached to nouns. But it does not pluralise a singular noun. However, the Possessive S converts a noun into a kind of adjective:

Let's observe the following sentences:
  • John has a bicycle.
  • John’s bicycle is blue. (the bicycle of John is blue.)

In the first sentence, the verb is has, the subject is John. Therefore, John is used as a noun.

In the second sentence, however, the verb is is, and the subject is bicycle. The word John’s is describing the word bicycle. This simply means that by adding the ’s, we converted an ordinary noun into an adjective.

By virtue of these demonstrations (we have observed), the difference between the Noun S and the Possessive S is the use of a punctuation mark, which is known as an apostropheOpens in new window.

Important Hint!  

Note that to make a plural noun possessive, we do not necessarily add ’s. We simply add an apostrophe (’), as the S is already there. (The boys’ bicycles are blue [The bicycles of the boys are blue.])

4.  The Verb S The Verb S–ending is a rather tricky one. It is reverse of the way we generally think of s–endings. First and foremost, it is added to Verbs, not nouns. Secondly, it makes a verb becomes singular.

The basic rule is, when the subject of a present tense verbOpens in new window is a singular noun, the verb takes an S–ending:
Examples include:
  • The pianist plays pianos.
  • The doctor treats patients.
If the present tense verb has a plural noun for a Subject, the verb gets No S–ending:
Examples include:
  • The pianists play pianos.
  • The doctors treat patients.

Note that this means that between a verb and its subject there is just only one S–ending to go around. Either there is an S on the verb, or there is an S on the subject.

Examples include:
  • Her honeymoon seems extravagant.
  • Their honeymoons seem extravagant.

On the other hand, if a singular noun ends with a Natural S, it has no S–ending. So its verb would still need to be tagged with an S–ending:

Examples include:
  • The boss cajoles his employees.
  • The bosses cajole their employees.

Further Rules of Subject Verb Agreement

Although the basic rules of subject–verb agreement are fairly straightforward, there are situations in which the rules are not easy to apply.

Sometimes, scanning through the words in search of an s–ending on the subject to decide whether the verb needs an s–ending will prove futile because there are a few exceptions.

1.  The Verb To Be The Verb To be is irregular, and it presents special problems in subject–verb agreement. Because it is irregular, we can’t just addd an S–ending or not. The S–forms are completely different words (as in the case of is and are).

Likewise, unlike any other verb in English, the verb to be has an s–form and a non–s form in the Past Tense:

Here are a few examples below:
  • One typewriter is not enough.
  • Two typewriters are enough.
  • One typewriter was not enough.
  • Two typewriters were enough.

2.  Am. — Note that Am, the fifth form of the verb to be, is used only in the present tense when we have I as the subject, for example: “I am studying.”

Using am when the subject is I tends to bring up a high–point about Subject–Verb Agreement. But what happens to the verb when its subject is a pronoun?

Since pronouns don’t get s–endings to make them plural, and since some pronouns (like you) can be used as either singular or plural, the rules we’ve learned so far won’t help us when a pronoun is the subject of a present tense verb.

But the problem isn’t much difficult;

    For example:
  • a)  He travels on business quite often.
  • b)  This idea is interesting.
    For example:
  • a)  They travel on business occasionally.
  • b)  Those are not interesting.
    For example:
  • a)  I think.
  • b)  I am.
  • c)  I was.

3.  Compound Subjects — A sentence with a compound subject takes the following form:

subjectandsubject+ Verb

This means, the whole subject consists of two nouns connected by the word and.

When it comes to subject–verb agreement, compound subjects (nouns connected by and) are considered plural. That means their present tense verbs do not take s–endings; that is, they take plural verbs.

Examples include:
  • The accountant and her two assistants work hard.
  • The forklifts and conveyor need repair.
  • All sales representatives and their families are invited to the company picnic.

Looking at the above examples, the fact is, these s–endings are just an extra clue. The and alone tells us not to put an s–ending on the verb.

4.  Compound Subjects Connected by Or and Nor When the nouns in a subject are connected by or, the rules change dramatically.

Observe the following variations:
  • My secretary or my assistant screens my calls.
  • My secretaries or my assistant screens my calls.
  • My secretary or my assistants screen my calls.
  • My secretaries or my assistants screen my calls.

Can you sight the pattern? Notice the word secretary has no effect on the verb; whether it has an s–ending or not doesn’t really matter.

The word assistant is what counts here. When assistant has no s– ending (the first two examples), the verb gets an s–ending. When assistants is used with an s–ending (the second two examples), the verb gets no s–ending.

This is because assistant is the noun closest to the verb.


This rule also applies with the expression “either … or …”:

Practical Example
  • Either your software or our drivers are not updated.
    (The noun drivers is closest to the verb; because drivers has an s– ending, we use a verb with no s–ending, are.)

This rule also holds true, even with nor and the expression “neither … nor …”:

  • Neither I nor my partner recalls your order.
    (Here, partner is closest to the verb, so recalls gets an s–ending.)

Note also that when the subject concerns a space of time, a sum of money, a measurement, weight, volume, or fraction, we usually use a verb with an s–ending.

Observe the examples below:
  • Two years in a military camp seems like eternity.
    (Here a singular verb is used because we think of the years as one unit of time. So the subject (two years) is singular, it goes with an s–ending verb.)
  • These last four years have been filled with adventure.
    (Here we’re thinking of each individual year, so we use the plural verb.)
  • One half of the class was absent.
    (An s–ending verb is used here because the subject is thought of as a singular unit.

  • Ten dollars is enough to cover the expense.
    (It’s true the money may be ten individual bills, but we take it as one lump sum of money, so the subject becomes singular, and a verb with an s–ending is used.)
A Few Exceptions

Watch out for the word “There”. It is usually the first word of a sentence, but this does not make it the subject.

Consider the sentence below:
  • There has been traffic on the bridge.

You probably already know that there is actually an adverb. In the sentence above, the verb is has been; the subject (what has been?) is traffic. So being a singular subject, it requires a singular verb (has been).

Sentences that begin with there are called Inverted Sentences because in any situation where they occur, the subject is the noun after the verb. Many inverted sentences can be reversed and put back into normal subject–verb order:

Practical Examples:
  • There is a refrigerator in the kitchen.
  • A refrigerator is in the kitchen.
  • There are two theories relevant to this argument.
  • Two theories are relevant to this argument.

Reversing an inverted sentence (at least mentally) can help us decide whether the verb needs an s–ending.

In any case, note that: When a sentence begins with “there”, the subject usually comes after the verb. You may need to look or think ahead when deciding whether or not the verb needs an s–ending.