Identifying Subject-Verb Agreement Errors

It's important that the subject and verb in every sentence agree in number. While it's often easy to make this happen, there are a few situations in which it can be tricky to achieve subject-verb agreement. This lesson explains how you can be sure to pair the right verb with a subject.

Subject-Verb Agreement

Do you remember when you were a kid playing with activity books? Did you ever play 'connect the dots?' That activity required you to figure out which two dots to connect at a time, even though there may have been a bunch of dots all clustered around.

Sometimes, to make sure that you've written a sentence correctly, you'll have to connect the dots between certain parts of a sentence, even if those parts aren't right next to each other. The parts of a sentence that essentially have to connect here are the subject and the verb. The subject of a sentence is what the sentence is about. It usually, though not always, performs the action of the verb. A verbis a word that expresses an action or occurrence.

Our connect-the-dots analogy comes into play here with the fact that the subject and verb in a sentence have to agree in number. In other words, if you have a singular subject, it has to connect with a singular verb. Likewise, a plural subject will require a plural verb. (Remember that singular means just one, while plural means more than one.)

This is simple enough to do, but occasionally, it may feel a bit like playing 'connect the dots' when your subject is in one spot in a sentence and your verb is some distance away. We'll discuss how to make sure that the connection always gets made.

Simple Sentences and Compound Subjects

Just remember that while we make most nouns plural by adding an 's' - like when we turn the singular noun 'apple' into the plural noun 'apples' - verbs often work in the opposite way. Often, a singular verb will end in an 's' while the plural version will be without the 's.' For example, we would say, 'This apple tastes good,' or 'These apples taste good.' Just don't get confused about which verbs are singular or plural by looking at them the same way you would at nouns.

Some sentences have compound subjects, which are subjects that consist of more than one word. Compound subjects are typically joined by 'and' or 'or.' A compound subject that has parts joined by 'and' would need to be matched with a plural verb. Here's an example: 'My cat and my dog are asleep.' Our compound subject 'My cat and my dog' is correctly matched with the plural verb 'are' here.

If you have a compound subject that's joined by 'or,' look at whether the component parts of the compound subject are singular or plural. If both parts of a compound subject joined by 'or' are singular, then you would use a singular verb. For example, I might say, 'Either Mr. Garcia or Ms. Jackson is in charge of the math club.' If both parts of a compound subject joined by 'or' are plural, then you would use a plural verb. For example, you might say, 'I think that either sharks or tigers are the scariest animals.'

So what do we do when one part of a compound subject joined by 'or' is plural and the other part is singular? Check out the sentence, 'Either Captain Davis or the lieutenants (blank) on duty tonight.' The first part of our compound subject, 'Captain Davis,' is singular, while the second part, 'lieutenants,' is plural.

Look at whichever part of the compound subject is closer to the verb. Make the verb agree with the part of the subject that is closer to it. In this case, it's the plural part of our compound subject - 'lieutenants.' Our completed sentence would therefore take the plural verb 'are.' 'Either Captain Davis or the lieutenants are on duty tonight.'

If we were to flip the order of the parts of the compound subject in our sentence, we would need to change our verb, too. In that case, our sentence would be, 'Either the lieutenants or Captain Davis is on duty tonight.' Here, because the singular part of the subject, 'Captain Davis,' is closer to the verb, we need a singular verb.

Subject-Verb Inversion

In some sentences, the subject and verb get flipped in terms of order, and the verb comes before the subject. This happens with questions, for example. No matter what order everything is in, though, we still need to be sure that in each sentence, our subject and verb agree in number. For example, I might ask 'Where are my books?' In this question, the subject is 'books' and the verb is 'are.' They're both plural, so the subject and verb in this sentence - even though the usual order is inverted - are in agreement.

Sentences that start with the word 'there' typically also feature an inverted subject-verb order. Again, the process is simple. Just connect the dots to identify the subject and verb and make sure that they agree in number. For example, in the sentence, 'There is a simple expla

Interrupting Prepositional Phrases

Connecting the dots to make sure that you correctly identify the subject and verb in a sentence in order to make them agree is especially important when other words and phrases come in between them. Take a look at the following sentence: 'The cost of medications (blank) risen recently.' To figure out whether we need a singular or plural verb, we'll first need to determine what our subject is.

Many people might glance at this sentence, see the word 'medications,' and decide that the sentence would correctly read 'The cost of medications have risen recently.' The assumption there would be that because 'medications' is plural, we'd need the plural verb 'have.'

Look again, though. Is 'medications' actually the subject of the sentence? Is the speaker saying that medications have risen or something else? In this sentence, the word 'of' is a preposition and the words 'of medications' is a prepositional phrase. (A preposition is a part of speech that shows how nouns or pronouns in a sentence are related to other words in the sentence.) Remember that a word in a prepositional phrase can never be the subject of the sentence in which the phrase appears. The word 'medications,' therefore, is not our subject in this sentence.

Instead, the subject is 'cost.' This makes sense because this sentence is really telling us that the cost has risen. The word 'cost' is singular, so we need a singular verb, 'has.' The corrected sentence would be 'The cost of medications has risen recently.' Here's one more example. 'Glitches in my computer (blank) causing problems.' What's the subject of this sentence? Remember that 'in my computer' is a prepositional phrase, so we need to ignore it for a moment.

The subject is 'glitches,' and that's a plural noun, so we need the plural verb 'are' here. The correct sentence would be 'Glitches in my computer are causing problems.' Remember not to be thrown off by the fact that a singular noun, 'computer,' sits right next to the verb. If a particular noun is not the subject, then we don't worry about it when figuring out how to make the subject and verb agree in number.

Indefinite Pronouns

You may recall that a pronoun is a word that takes the place of or refers to a noun. There's a specific type of pronoun that may cause a bit of confusion when it comes to subject-verb agreement. Indefinite pronouns are pronouns that do not refer to a specific person or thing. Here are some examples:

• Anybody
• Anyone
• Anything
• Everybody
• Everyone
• Nobody
• Nothing
• None
• Somebody
• Someone and
• Something

All of these are singular indefinite pronouns.

We tend to think of some of these indefinite pronouns, like 'everybody' and 'everyone,' as referring to a lot of people instead of being singular. Actually, though, in terms of grammar, these indefinite pronouns are technically singular, so we need to match them up with singular verbs in sentences in order to ensure that we don't have subject-verb agreement problems.

For example, we'd say, 'Everybody has the right textbook for class.' Not only does that sound right, but it also checks out grammatically. 'Everybody' is a singular indefinite pronoun and it's the subject of our sentence, and 'has' is a singular verb.