We can help you get into your dream school.

Start Magoosh SAT or Magoosh ACT Prep today!

David Recine

ACT English Grammar Rules: Singular and Plural Forms

Spotting and correcting grammar mistakes is a significant part of ACT English. Questions that test your ability to properly use singular and plural forms are especially common in the English section. You’ll often be presented with mistakes related to singular/plural word form errors, either in the text or in the answer choices. There are a few rules you should be aware of as you look for these mistakes and their proper corrections on the exam.



Plural Nouns Have Plural Verbs While Singular Nouns Have Singular Verbs

This is a rule that ACT English loves to break in its prompts. You need to pay close attention to plural forms in the readings and questions.

Suppose the subject of a sentence is a plural noun phrase, such as “my mother and father.” In that case, the verb that describes the actions of “mother and father” must also be plural. A common mistake you’ll see in an ACT English passage might read “My mother and father was enthusiastic about the school project as soon as I mentioned it to them.” Do you see the problem with was? It should be were. That’s the correct plural past tense form of to be. An improper use of a plural verb might appear in a follow-up sentence such as “To this day, my mother are proud of the work we did together on the school project.” Are would need to be changed to is, the present-tense verb that matches the singular subject mother.


If There Is A Modal Before The Verb, The Verb Will Not Have A Singular Or Plural Form

This rule is easy to forget and ACT English questions with (Reviewing Common Modals in Act English, Part 1) modals (Reviewing Common Modals in Act English, Part 2) often trick students with this rule. So remember: if there is a modal word before a verb, the verb will appear in its bare form, without any “s” added at the end to mark the verb as singular. This is also true even when the subject of a sentence is singular.

Let’s look at an example with the modal might. It’s perfectly grammatical to say “they might do that” or “she might do that.” The bare verb form do is used with both a plural subject like they and a singular subject like she if a modal is present. Remove the modal, however, and you’ll still need to follow the rule for singular verbs that go with singular subjects. Without the modal, these two statements have different verbs form, with “they do that” and “she does that.”


Plural Nouns Should Be Followed By Plural Pronouns, Singular Nouns Should Be Followed By Singular Pronouns

Pronouns must have the same plural or singular nature as the nouns they refer to. You wouldn’t say “The last two U.S. presidents served two terms, and he each had a total of eight years in office.” You would of course have to say that they each served for 8 years. Also, you wouldn’t say “The badger is a common animal in North America and they dig burrows into the ground.” You’d say that it digs holes, because you used a singular subject the badger.

On the surface this rule seems more straightforward than the rules for singular verbs. There are no exceptions of any sort to this pronoun referent rule. However, this rule is one of the easiest to forget as you read ACT English passages, and mistakes in singular and plural pronouns are some of the hardest to spot. This is because ACT English won’t necessarily present a noun and its pronoun in the same sentences, as seen in my examples above. Instead, you’re more likely to see the mistakes presented in longer segments of writing, like these:

  • The last two U.S. presidents, George W. Bush and Barack Obama, were both re-elected, serving two full terms in office. A single U.S. presidential term is four years long. This means he had a total of eight years each as president.
  • The badger is a species of animal common in North America. Digging burrows into the soft soil of the American Midwestern landscape, they live underground.

In the complex academic passage on the ACT, pronouns almost never appear in the same sentence as the nouns they reference. As a result, it’s easy for your sense of singular and plural to get “lost” in the writing maze.

To make sure you can keep track of the different singular and plural forms on the ACT, study these rules carefully. Recognizing these rules and understanding when they’ve been broken can really help your score on the ACT.


Improve your SAT or ACT score, guaranteed. Start your 1 Week Free Trial of Magoosh SAT Prep or your 1 Week Free Trial of Magoosh ACT Prep today!

magoosh logo checks

About David Recine

David is a test prep expert at Magoosh. He has a Bachelor of Social Work from the University of Wisconsin-Eau Claire and a Masters in Teaching English to Speakers of other Languages from the University of Wisconsin-River Falls. He has been teaching K-12, University, and adult education classes since 2007 and has worked with students from every continent. Currently, David lives in a small town in the American Upper Midwest. When he’s not teaching or writing, David studies Korean, plays with his son, and takes road trips to Minneapolis to get a taste of city life. Follow David on Google+ and Twitter!

Magoosh blog comment policy: To create the best experience for our readers, we will approve and respond to comments that are relevant to the article, general enough to be helpful to other students, concise, and well-written! :) If your comment was not approved, it likely did not adhere to these guidelines. If you are a Premium Magoosh student and would like more personalized service, you can use the Help tab on the Magoosh dashboard. Thanks!