Introduction to 7 Must-Know Grammar Skills for ACT® English

The English language contains more than three hundred grammar rules. How on earth will you remember them all for the ACT® English exam?

Good news: At first glance, the ACT® English section may seem daunting, but if you keep in mind the seven simple grammar skills outlined in this guide, you’ll be well on your way to a 36!

The ACT® English section will test your expertise in English grammar and style. You’ll be asked to replace words, change syntax, choose homophones, reconstruct comparisons, and more.

This ACT® study guide will explain all of the trickiest grammar rules, offer examples, and teach you what you need to know to ace this part of the exam.

Number 1: Subject-Verb Agreement

Verbs and nouns change depending on whether they refer to one thing (singular) or more than one thing (plural). For example, a girl eats a hotdog, but three girls eat hotdogs.

Subject-verb agreement just means that plural nouns correspond to plural verbs, and singular nouns correspond to singular verbs.

ERROR: The students takes the exam.

SOLUTION: The students take the exam.

Keep this in mind for pronouns as well.

ERROR: She study so hard every morning.

SOLUTION: She studies so hard every morning.

Number 2: Choosing the Correct Word

Not-Quite-Synonyms

Sometimes the ACT® English section will present you with an underlined word, and offer several words that have almost the same meaning. Be wary: even if all of the answer choices have nearly the same definition, only one word will be correct in context!

ERROR: We puddled our resources and made enough money.

SOLUTION: We pooled our resources and made enough money.

Homophones

Conversely, the ACT® English section might give you a list of words that all sound the same, and you’ll have to choose the correct one.

ERROR: The explorer’s story peaked my interest.

SOLUTION: The explorer’s story piqued my interest.

Idioms

You probably use idioms on a daily basis, even if you don’t realize it. For example, maybe you get “sick as a dog” during flu season. This section will test your knowledge of common expressions.

ERROR: The shabby apartment was a far cry to the mansion where the tycoon had once lived.

SOLUTION: The shabby apartment was a far cry from the mansion where the tycoon had once lived.

ERROR: He and his brother never quite saw eye and eye.

SOLUTION: He and his brother never quite saw eye to eye.

There are usually only a few idiomatic error questions on the ACT® exam, and relying on your ear will help you go a long way in this section – you’ve probably heard, or said, many of these expressions before.

Number 3: Punctuation

Punctuation is one of the trickiest parts of ACT® English grammar because there are so many rules to memorize. The good news is that once you commit the following key rules to memory, you’ll breeze through this section.

What you need to know:

• Punctuation revolves around two parts of a sentence: an independent clause and a dependent clause.
• An independent clause can stand on its own as a complete sentence. It includes, at the bare minimum, a subject and a verb.
• A dependent clause does not make sense if it stands on its own.

Independent clause: The dancer broke her ankle.

Dependent clause: Because of slippery floors.

Full sentence: The dancer broke her ankle because of slippery floors.

Sentence Fragment

A dependent clause standing on its own is a sentence fragment. To fix a sentence fragment, attach the dependent clause to an independent clause or turn it into its own independent clause.

ERROR: Wished upon a star.

SOLUTION: The sailor wished upon a star.

Run-On Sentence

If two or more independent clauses are joined without a semicolon, colon or conjunction, then that is a run-on sentence. Divide it into two sentences, or add a semicolon, colon or conjunction.

Conjunctions: and, or, but, nor, so, for, yet, after, because, before, although, as, if, once, until, unless, when, whenever, wherever, whether, while.

ERROR: I let him borrow my iPhone he lost it the same day.

SOLUTION: I let him borrow my iPhone, and he lost it the same day.

Comma Splice

If a comma joins two independent clauses, this type of run-on sentence is called a comma splice. Split the independent clauses into separate sentences, or add a semicolon, colon or conjunction.

ERROR: I hate flying, I never get on airplanes!

SOLUTION: I hate flying, so I never get on airplanes!

SOLUTION: I hate flying; I never get on airplanes!

Essential v. Nonessential Clauses

An essential clause is a phrase that cannot be removed from a sentence without changing the meaning of the sentence. Do not put commas around an essential clause.

ERROR: The lemonade, that has been sitting out all day, tastes terrible.

SOLUTION: The lemonade that has been sitting out all day tastes terrible.

A nonessential clause can be removed without changing the overall meaning of the sentence. Surround this clause with commas.

ERROR: My mother who used to be a ballerina still loves to dance.

SOLUTION: My mother, who used to be a ballerina, still loves to dance.

Shortcut: If a clause starts with “that”, then it’s essential and doesn’t take commas. If a clause starts with “which” then it is nonessential and takes commas.

Colons

Use colons after an independent clause. A colon can precede a list.

ERROR: I bought: candy, bubble gum and soda pop.

SOLUTION: I bought too many sweets: candy, bubble gum and soda pop.

A colon can also precede another independent clause that is directly related to the first independent clause.

ERROR: I couldn’t believe my eyes, the swarm of bees grew and grew.

SOLUTION: I couldn’t believe my eyes: the swarm of bees grew and grew.

Apostrophes

If you join two words, you’ll make a conjunction – “you’ll” is the perfect example. “You’ll” is a combination of “you” and “will”. In every conjunction, an apostrophe will always replace the letters that are left out.

ERROR: Whos in charge here?

SOLUTION: Who’s in charge here?

You’ll also use apostrophes to form possessives.

If a proper or improper noun ends with a letter other than S, add an apostrophe and an S.

ERROR: That’s the children’ playroom.

SOLUTION: That’s the children’s playroom.

If a noun ends in S, add an apostrophe after the S.

ERROR: The rain ruined James books.

SOLUTION: The rain ruined James’ books.

Number 4: Relative Pronouns

You know that pronouns correspond to certain objects. For example, if you were talking about a female teacher, you would use the pronouns she and her.

But a relative pronoun connects a clause to a noun. Relative pronouns include that, which, where, when, whose, and who/whom.

Each relative pronoun can only be used with a certain type of noun. Although some nouns can take more than one type of relative pronoun, the ACT® English section may try to trick you by using the wrong relative pronoun in a sentence.

“That” refers to a noun.

ERROR: This is the book whom we had to read for class.

SOLUTION: This is the book that we had to read for class.

“Which” refers to any non-person noun.

ERROR: Where is the bank in where in the robbery occurred?

SOLUTION: Where is the bank in which the robbery occurred?

“Where” refers to a specific place.

ERROR: Aaron Burr said, “That is which the duel will occur.”

SOLUTION: Aaron Burr said, “That is where the duel will occur.”

“When” refers to a specific time.

ERROR: That was the moment where she realized the truth.

SOLUTION: That was the moment when she realized the truth.

“Whose” is possessive and refers to people, animals or things.

ERROR: Who’s dog is this?

SOLUTION: Whose dog is this?

“Who and whom” refer to people.

ERROR: Who was the man that was running for president?

SOLUTION: Who was the man who was running for president?

While we’re on the topic of who and whom, you might be wondering when exactly to use each word. “Who” refers to the subject of a sentence, while “whom” refers to the object. In other words, if you can replace the person with “he or she,” use “who.” If you can rewrite it with “him or her,” use “whom.”

ERROR: That’s the man to who I mailed the letter.

REWRITE: I mailed the letter to him.

SOLUTION: That’s the man to whom I mailed the letter.

ERROR: Whom wants to eat?

REWRITE: He/she wants to eat.

SOLUTION: Who wants to eat?

Number 5: Clarity

The ACT® test will also test you on sentence clarity by asking you about ambiguous pronouns, redundancy and dangling participles.

Ambiguous Pronouns

Even if a pronoun is grammatically correct, the ACT® will consider it incorrect if the pronoun makes the sentence unclear. If a pronoun could refer to one or more people or things, then change the pronoun to clarify what it’s referencing.

ERROR: Mary and Elise both agreed that her strudel recipe was best.

SOLUTION: Mary and Elise both agreed that Mary’s strudel recipe was best.

In the first sentence, it’s unclear whether “her” refers to Mary or Elise.

Redundancy

A redundant sentence is one that will make you say, “All right, all right! I get it already!” A redundant sentence states the same thing twice or more. It could include a list of synonyms, or it could include a verb and an adverb that mean the same thing.

ERROR: Thomas Jefferson rushed quickly into the room.

SOLUTION: Thomas Jefferson rushed into the room.

This is redundant because if Thomas Jefferson rushed, then that means he moved quickly; there’s no way to rush slowly!

Dangling Participle

A dangling participle occurs when the opening phrase of a sentence does not refer to its intended subject.

ERROR: After breaking into the apartment, the bandit’s bag was soon full of stolen jewelry.

SOLUTION: After breaking into the apartment, the bandit filled her bag with stolen jewelry.

SOLUTION: After the bandit broke into the apartment, her bag was soon full of stolen jewelry.

Because “the bandit’s bag” is the subject of the first sentence, that sentence makes it seem as if the bandit’s bag is breaking into the apartment. In order to fix it, you should change the subject in the independent clause to “the bandit” or put “the bandit” into the dependent clause.

Wordiness

If you can make a sentence more concise without losing its meaning, then do so.

ERROR: I often experience terror when watching horror films.

SOLUTION: Horror films terrify me.

Number 6: Consistency

The ACT® English section will test you on whether paragraphs, or even sentences, are consistent throughout.

Tense Consistency

A paragraph should be entirely in one tense. For example, if an underlined sentence is in present tense and the sentences around it are in past tense, then change the underlined sentence to match.

ERROR: Thomas Jefferson caught James Madison’s eye. Jefferson is about to announce his run for the presidency. Madison nodded before Jefferson even said a word.

SOLUTION: Thomas Jefferson caught James Madison’s eye. Jefferson was about to announce his run for the presidency. Madison nodded before Jefferson even said a word.

Parallelism

A sentence is more powerful and pleasing to the ear when it is parallel. No, we’re not talking geometry – parallelism is when you structure your sentence using grammatically similar or identical elements throughout.

For example, the phrase “like father, like son” is parallel. So are “what goes around comes around” and “we want the robber dead or alive”.

The ACT® English section will ask you to make sentences parallel.

ERROR: The hawk soared high and with great speed.

SOLUTION: The hawk soared high and fast.

SOLUTION: The hawk soared with great height and with great speed.

The first sentence is incorrect because high is a single adverb describing how the hawk soared, but “with great speed” is a prepositional phrase. To correct that sentence, turn “high” and “with great speed” into single adverbs or turn them both into prepositional phrases.

Number 7: Comparisons

A comparison is when a writer puts two people, places or things side by side, and observes how they relate to each other. For example, you are older than your younger sibling. Simple, right? Just remember that different comparisons require different words to be grammatically correct.

Keep this list in mind:

• Compare to/with: Compared to my dog, I’m pretty well behaved.
• In contrast to: In contrast to presidential elections, municipal elections have very little voter participation.
• Just as/like: Martin Luther King Jr. was just like his father.
• Similar to: The musical Rent was not very similar to the musicals that came before it. (Adjective) than: My brother is sillier than I am.
• Different from: The Brontë sisters were very different from each other.

Many people want to say “different than”, but you can only use “different than” if you use “than” as a conjunction before a clause.

ERROR: Christmas in Miami, Florida was very different than Christmas in Juno, Alaska.

SOLUTION: Christmas in Miami, Florida was very different than I experienced in Juno, Alaska.

Conclusion

Now you know the seven most important grammar skills on the ACT® English section, and you’re well on your way to getting a 36! Remember to always check for subject-verb agreement, choose the correct word, be mindful of punctuation, specify relative pronouns, clarify sentences, use consistent structure and make proper comparisons.

Good luck!

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