The 8 Most Common Mistakes You Make on ACT English


Over the past five years, I've tutored dozens of students on the ACT and seen them miss the same types of questions over and over again. The ACT English section really only tests a handful of concepts, so it's easy to make the same exact mistake on three or four questions—which really hurts your score.

Don't worry, though! I've come up with eight simple rules you can follow to help you avoid the most common problems on the ACT English and automatically raise your score 1-2 points. Use my ACT English strategies and practice on a lot of realistic questions, and you'll raise your English score.

A lot of common mistakes revolve around going with the answer that sounds right rather than the choice that follows the rules. To help you spot the difference, I'll go through the mistakes most students make in order of frequency and explain how you can avoid them:

  1. Avoiding NO CHANGE
  2. Not removing redundant or irrelevant words
  3. Inserting too many commas
  4. Incorrectly punctuating independent clauses
  5. Mixing up it's and its
  6. Using they instead of he or she
  7. Glossing over the question
  8. Missing modifier errors


Mistake #1: Assuming Every Underlined Portion Includes an Error

NO CHANGE seems like it must be wrong, but it's actually correct slightly more than 25% of the time. Don't automatically rule out choice A or F, and don't second guess yourself if you have NO CHANGE as the answer for multiple questions in a row.

Instead, if you can't find an error and think NO CHANGE might be the best choice, look at the differences between the answers and try to determine what type of question it is.

Are all the answers verbs? It's probably a verb tense or subject-verb agreement question. Does each answer have commas placed in different locations? It's likely a comma question. (Keep in mind, however, that some questions test more than one concept.)

Once you know what kind of question it is, you can determine whether the original version avoids the error. Is the verb properly conjugated? The commas properly placed? 

The trick to not being confused by NO CHANGE is treating it like any other answer. If the best version of the underlined portion is the original one, then pick A.

For more information on the frequency of NO CHANGE, check out our full analysis.


Mistake #2: Leaving in Extra Words

Relevance and redundancy are two of the least intuitive concepts on the ACT English section. Questions that test these topics require you eliminate totally grammatically acceptable phrases that often seem to add information.

The key to understanding how to approach these questions is recognizing that not all information is useful. Take a look at this example sentence:

Every spring, I go through my yearly house-cleaning ritual and clean my home.

This sentence is perfectly grammatical and easy to understand. However, it repeats certain ideas unecessarily. "Every spring" is by definition "yearly," so we don't need the second word. Moreover, the "ritual" is explicitly described as "house-cleaning," so "and clean my home" is redundant.

Every spring, I go through my house-cleaning ritual.

If an answer restates something that's already been established or adds information that isn't directly related to the point at hand, it's probably wrong. Try taking the extra words out and see if the sentence still makes sense (both grammatically and logically). If so, pick the answer that leaves out the unnecessary words.

Don't be afraid to choose OMIT the underlined portion, if you think the passage works without the whole underlined section.

For a more in depth take on redundancy questions, see our full post on the topic.


Mistake #3: Adding Unnecessary Commas

Many students believe that you should put a comma any place in a sentence where there's a pause, but this approach will result in your missing a lot of questions. Take a look at the following example:

I know Callie thought that accusing Jon, of stealing the headphones, would just cause more problems.

These commas may seem correct, but they're actually unnecessary. Although this sentence is fairly long, it doesn't require any commas at all:

I know Callie thought that accusing Jon of stealing the headphones would just cause more problems.

The truth is that commas are only necessary in very specific situations. A good rule of thumb is "When in doubt, leave it out!"

If comma questions are tripping you up, our complete guide to commas on the ACT can help you understand when you need them and when you don't.


body_moremore.jpgThis is not a wise attitude to take towards commas.


Mistake #4: Connecting Independent Clauses Incorrectly

One of the most common ACT English comma issues is called a comma splice, it occurs when a comma is used to connect two independent clauses (this sentence is an example!). There are four correct ways to connect two complete thoughts: a period, a semicolon, a colon, and a coordinating conjunction with a comma.

Let's look at some alternate versions of the sentence above:

Incorrect: One of the most common comma issues is called a comma splice it occurs when a comma is used to connect two independent clauses.

Incorrect: One of the most common comma issues is called a comma splice and it occurs when a comma is used to connect two independent clauses.

Correct: One of the most common comma issues is called a comma splice. It occurs when a comma is used to connect two independent clauses.

Correct: One of the most common comma issues is called a comma splice; it occurs when a comma is used to connect two independent clauses.

Correct: One of the most common comma issues is called a comma splice: it occurs when a comma is used to connect two independent clauses.

Correct: One of the most common comma issues is called a comma splice, and it occurs when a comma is used to connect two independent clauses. 

For more information on comma splices and other forms of run-on sentences, take a look at our in depth article


Mistake #5: Confusing It's, Its, and Its'

The differences between can seem complicated, especially if you haven't studied them in a while, but they're actually quite straight forward.

Its, with no apostrophe, is a possessive pronoun. It's equivalent to "his" or "her," which you'll notice don't have apostrophes either.

It's, with an apostrophe before the s, is a contraction of "it is" or "it has." Contractions always have to have an apostrophe to replace the dropped letter or letters.

Its', with an apostrophe after the s, isn't a real word. This construction will appear as an answer on the ACT but it's always wrong.

When trying to determine whether the word needs an apostrophe, you should replace it with with "it is" (or "it has," depending on context) and see if the sentence makes sense. If so, "it's" is correct. If not, "its" is. Let's go over an example:

The cat pinned back its' ears to show displeasure. 

We know "its'" can't be correct—we just have to determine whether it should be "it's" or "its." Let's plug in "it is" and see if that makes sense:

The cat pinned back it is ears to show displeasure. 

That version doesn't make sense. "Its" is the correct choice, since the pronoun is meant to indicate that the ears belong to the cat:

The cat pinned back its ears to show displeasure. 

For more information on its vs. it's and other apostrophe issues, check out our post on punctuation.


body_confuseddoe.jpg This deer may be confused, but you don't have to be!


Mistake #6: Using They or Their as a Singular Pronoun

When we speak, we routinely use the plural pronouns "they," "their," and "them" to refer to individuals on uncertain gender (e.g. the child, the teacher, the inventor).  In written English, however, this usage is considered a pronoun agreement error: the noun is singular, but the pronoun replacing it is plural.

Take a look at this example sentence:

Incorrect: At the end of many fantasy novel, the protagonist must face their nemesis in single combat.

Correct: At the end of many fantasy novels, the protagonist must face his or her nemesis in single combat.

Though it may seem overly complicated, the second version of the sentence correctly matches noun and pronoun. 

Pronoun agreement is frequently tested and can be tricky, so consider checking out our complete guide to pronoun agreement on ACT English.


Mistake #7: Not Reading the Question

Because most of the questions on ACT English revolve only around underlined portions of the passage, it’s easy to gloss over questions when they appear. 

However, as with the other sections of the ACT, it's extremely important to carefully read the questions and think about what they're asking. Usually, the best indication of the answer is right there in the question.

This rule is especially vital to answering questions that ask about which version of a sentence or phrase is best. It can be tempting to simply pick the answer you think sounds best, but this approach will usually give you the wrong answer. Instead, look at what the question is asking for, e.g. "specific details" or "information that sets up a contrast."

The ACT English section includes a pretty wide range of questions that use this format, so if you're struggling with these types of questions take a look at some of our general advice on the ACT English questions and passages.


Mistake #8: Misplacing Modifiers

Misplaced and dangling modifiers—descriptive words or phrases that are incorrectly placed in a sentence—are another type of weird error that often doesn't seem wrong. Nonetheless, the ACT includes them fairly frequently, so keep this key rule in mind: a modifier must be next to whatever it modifies

Incorrect: While walking, the banana peel tripped me.

Correct: While walking, I tripped on the banana peel.

Dangling modifiers (which, like the example above, are introductory phrases that are separated from the thing they're modifying) are especially tricky. Be on the lookout for sentences that begin with descriptive phrases—they must be followed by the noun they describe.

For further details on both dangling and misplaced modifiers, see our grammar guide to ACT English faulty modifiers.


body_keepgoing.jpgKeep on going towards the score you want! (Image: Piermario/Flickr)


What's Next?

Take the time to get comfortable with other frequently tested concepts like subject-verb agreement and pronoun case.

Looking to build a study plan? Read our complete plan to studying for the ACT, review what the ACT English actually covers, and take a practice test (or five!).

If you're aiming especially high (or even if you aren't), make sure to check out these 9 key strategies from a perfect scorer.



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About the Author
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Alex Heimbach

Alex is an experienced tutor and writer. Over the past five years, she has worked with almost a hundred students and written about pop culture for a wide range of publications. She graduated with honors from University of Chicago, receiving a BA in English and Anthropology, and then went on to earn an MA at NYU in Cultural Reporting and Criticism. In high school, she was a National Merit Scholar, took 12 AP tests and scored 99 percentile scores on the SAT and ACT.

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