Get ACT practice questions and videos here!

Sign up or log in to Magoosh ACT Prep.

Magoosh ACT

ACT Grammar

On the ACT English Test as long as you know what underlined portion is incorrect, you won’t have to necessarily know how to fix it. Three choices will contain a grammar error, and one will be correct. Make sure to look out for these commonly-tested ACT grammar errors so you can ace the ACT English Test on Test Day!

Common ACT Grammar Elements

1.       Punctuation – You will need to fix misplaced, missing, or unnecessary punctuation on the ACT test. Review your usage rules for commas, apostrophes, colons, semicolons, dashes, periods, question marks, and exclamation points.

2.       Verb Forms – English has six tenses: past, present, future, present perfect, past perfect, and future perfect. Make sure the sentence uses the correct tense in the context of the time frame discussed.  Verbs must also agree with their subjects in number.

3.       Comparative/Superlative Form – Use comparative form (less, more) when comparing two items. Use the superlative form (most, least) when comparing three or more items.

4.       Pronoun Shifts – Pronouns must agree with their antecedents in person and number. Additionally, use the subject form when the pronoun is doing the action of the verb or after a linking verb like “to be.” Use the object form when a pronoun is the object of a verb, verb form, or preposition, or in comparisons between objects of verbs that are implicitly clear though not directly mentioned.

5.       Run-Ons – A sentence that has more than one independent clause improperly combined is called a run-on. A run-on can be fixed by making each independent clause its own sentence, by combining them with a semicolon, by making one clause dependent, or by joining the clauses with a coordinating conjunction.

6.       Fragments – A sentence fragment does not form even one independent clause. This is usually because it lacks a subject, a predicate verb, or does not express a complete thought. A fragment can be fixed by adding the missing element or by combining it with another sentence.

7.       Parallel Structure – Look for lists that are underlined on ACT English questions. Items in a list should always be in the same form. Comparisons should also be in the same form, meaning all verbs should be in either infinitive or participle form.

8.       Idioms – In English, certain words must go together in order to be grammatically correct. “Between…and”, “not only….but also…”, and “neither…nor” are three of the most-common. There is no complete list of Idioms, but you will usually be able to spot them because something will “sound” funny in the sentence. Trust your ear. If something sounds incorrect on the ACT English Test, it probably is!

9.       Organization – These questions are found on the ACT English Test, but they are more like reading comprehension problems. These questions ask about the coherence of ideas in a paragraph or transitional phrases.

10.   Wordiness – This isn’t really a grammar issue, but on the ACT, shorter is usually better. You want sentences to be as concise as possible without losing any meaning. Two words are redundant if they have the same meaning. When you see an answer choice option that says “OMIT” make sure to start there.

Of course the topic of grammar on the ACT goes much farther than these ten simple points, but hopefully this gets you started in the right direction.

Which ACT grammar is the most difficult for you? Let us know below!


Ready to get your highest ACT score? Start here.
About Magoosh ACT

Magoosh is a company of passionate educators, located in Berkeley, CA. We are here to provide you with everything you need to prep for the ACT, SAT, GRE, GMAT, and TOEFL! Be sure to follow us on Twitter @Magoosh.

Leave a Reply

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!