Even though the English language is complex, ACT English tests a specific set of grammar rules. Furthermore, it tests these rules the same way, over and over again.
In this complete guide, we’ve compiled the comprehensive list of ACT English grammar rules you need to know to ace the ACT English section. If you master all these rules and practice them with realistic ACT questions, you’ll have a huge advantage on the English section.Unlike other guides, we give you lots of examples to help you understand how grammar rules will show up on the ACT. After all, you need to master the ACT format to do well on the ACT.
The English rules tested on the ACT can be grouped into two categories: Usage and Rhetoric.
Usage skills are what are typically called «grammar rules,» such as punctuation, subject/verb agreement, and verb tenses.
Rhetorical skills have to do with style, organization, and writing logic. You’ll need to know how to organize sentences in a paragraph, connect two ideas together logically, and sequence paragraphs together.
We’ll start first with Usage skills, then move onto Rhetorical skills.
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Usage questions cover primarily grammar and punctuation—what we generally think of as correct English.
The ACT only tests very specific uses of certain kinds of punctuation. Those rules, and only those rules, are detailed below.
Use commas to separate words and word groups in a simple series of three or more items.
We had coffee, cheese, crackers, and grapes.
Use a comma to separate two adjectives when the adjectives are interchangeable.
It was a vibrant, massive painting.
When starting a sentence with a dependent clause, use a comma after it.
When Jim studied in the library for his chemistry quiz, it was very quiet.
Use commas to set off nonessential parts of the sentence.
The woman, knowing it was late, hurried home.
Apostrophes are used two ways on the ACT: to show possession and to create contractions. Many of the apostrophes issues are tested using the «Word Choice» skill further below.
To form possessives of nouns:
The kids’ toys
The tree’s leaves
Note that the singular possessive Laura’s has the apostrophe before the s, while the plural possessive kids’ has the apostrophe after the s.
To create contractions (show the omission of letters):
There’s a clown.
You’d love it.
Use a colon after an independent clause when it is followed by a list, a quotation, appositive, or other idea directly related to the independent clause.
The vote was unanimous: the older candidate had won.
Use a semicolon to join 2 independent clauses when the second clause restates the first or when the two clauses are of equal emphasis.
I’m not sure how to get there; let’s get directions.
Use a semicolon to join 2 independent clauses when the second clause begins with a conjunctive adverb (however, therefore, etc.) or a transition (in fact, for example, etc.).
The basement is scary; thus, I do not go down there alone.
Dashes are used to set off or emphasize the content enclosed within dashes or the content that follows a dash. Dashes place more emphasis on this content than parentheses.
Upon discovering the errors—all 124 of them—the publisher immediately recalled the books.
Use a period at the end of a sentence that makes a statement.
He will try again.
Use a question mark after direct questions.
Where are we?
Use (rarely) an exclamation point at the end of a sentence to express strong emotion.
A pronoun is a noun that can stand in for another noun. For example, the pronoun «she» can stand in for «the woman» or «Queen Elizabeth.» But, unlike nouns, pronouns change their form if they’re used in different ways. These are the ways that pronouns are tested on the ACT.
Subject vs. Object Pronouns
Nouns, in relation to verbs, can be subjects or objects. Subjects «do» verbs and objects have verbs «done» to them: a dog (the subject noun) chases (the verb) its tail (the object noun).
Regular nouns like dog or tail do not change depending on whether they are subjects or objects, but most pronouns do. For example, in the phrase «she likes him,» the woman is the subject, so the pronoun is she; in the phrase «he likes her,» the woman is the object, so the pronoun is her.
Error: Me and my parents ate dinner.
Corrected: My parents and I ate dinner.
Error: The tourists asked my friends and I for directions.
Corrected: The tourists asked my friends and me for directions.
Error: The Girl Scouts sold cookies to my sister and I.
Corrected: The Girl Scouts sold cookies to my sister and me.
Note above that all of the examples pair the faulty pronoun with another noun. This is almost always how the harder ACT pronoun questions test this skill.
That vs. Who
This concept is simple: who is the pronoun for a person or people, and that is the pronoun for everything else.
Error: The coach is the person that is in charge of the team’s schedule.
Corrected: The coach is the person who is in charge of the team’s schedule.
Error: The elephant is the animal who asks for the most treats.
Corrected: The elephant is the animal that asks for the most treats.
Error: The corporation is who owns this land.
Corrected: The corporation is what owns this land.
When we use pronouns more than once in a sentence, we have to use the same perspective throughout.
Error: If a person wants to succeed in corporate life, you have to know the rules of the game.
Corrected: If a person wants to succeed in corporate life, she has to know the rules of the game.
Error: Everyone should make their own decision.
Corrected: Everyone should make his own decision.
Error: Every student must study hard if they want good grades.
Corrected: Every student must study hard if she wants good grades.
Note: In the second example, that the error is the commonly-used «their» to mean a singular noun (everyone); while this is used in common, everyday speech, using «their» as a possessive pronoun for a single person is not formally accepted as grammatically correct on the ACT. These singular nouns that seem plural (such as nobody, anyone, and each person), as well as «their» instead of the singular «he» or «his,» are often tested in the hardest pronoun questions.
Wherever there is a pronoun, it should be obvious what the pronoun is «standing in» for.
Error: Ethel told Lucy that her pie was wonderful.
Corrected: Ethel told Lucy that Lucy’s pie was wonderful.
Error: The files arranged by the temporary workers were out of order, so we sent them back to the main office.
Corrected: The files arranged by the temporary workers were out of order, so we sent the files back to the main office.
Error: Once Nora and Elise go to live with their husbands, they have to convert to their ways of living.
Corrected: Once Nora and Elise go to live with their husbands, the husbands have to convert to their wives’ ways of living.
Verb Forms: Tense and Agreement
There are two main issues with verbs tested on the ACT: verb tense and subject-verb agreement. The subject is the noun that «does» the verb (below, the subject of the sentences is they.)
There are six basic verb tenses, two for each time period:
Simple Present: They sing.
Present Perfect: They have sung.
Simple Past: They sang.
Past Perfect: They had sung.
Future: They will sing.
Future Perfect: They will have sung.
All of these tenses are created out of three forms of «to sing»: sing (present), sang (past), and sung (past participle). As you can see, some of the correct verb forms are created by adding forms of the words «have» and «do.» The idea is to keep verbs in a single sentence within the same time period.
Error: The boy insisted that he has paid for the candy bars.
Corrected: The boy insisted (past) that he had paid (past perfect) for the candy bars.
Error: The doctor suggested bed rest for the patient, who suffers from a bad cold.
Corrected: The doctor suggested (past) bed rest for the patient, who suffered (past) from a bad cold.
Error: I told him that he can drop by any time and I will be happy to help him.
Corrected: I told (past) him that he could (past) drop by any time and I would (past) be happy to help him.
Nouns and verbs are both parts of speech with number: they are written differently if they refer to just one thing or multiple things. Subject/verb agreement just means that the noun and the verb have the same number (singular or plural). For example, one dog runs fast, but two dogs run fast.
Matching subjects and verbs are underlined, while verbs that don’t match subjects are bold.
Error: The climate in those cities are uncomfortably humid.
Corrected: The climate (singular) in those cities is (singular) uncomfortably humid
Error: There was a rat and three buckets of whitewash in the corner of the basement.
Corrected: There were (plural) a rat and three buckets of whitewash (plural) in the corner of the basement.
Error: Ms. Russell is trying to read a book outside but a swarm of flies keep distracting her.
Corrected: Ms. Russell is trying to read a book outside but a swarm (singular) of flies keeps (singular) distracting her.
These are pretty simple. Comparisons between two things are formed by the construction «x is more/less [adjective]/[adjective]-er than y.« For example, Bill is more friendly than Louis.
Comparisons between three or more things, however, are formed by the construction «x is the most [adjective]/[adjective]-est of the [things].» For example, Lucy was the most adept student in the class or The cheetah is the fastest land animal.
The ACT tests this skill by mismatching the types of comparison:
Error: Between butterflies and spiders, humans admire butterflies the most.
Corrected: Between butterflies and spiders, humans admire butterflies more.
Error: Cheetahs are the faster of all land mammals.
Corrected: Cheetahs are the fastest of all land mammals.
Error: Nationalists think theirs is the better nation of all.
Corrected: Nationalists think theirs is the best nation of all.
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These questions are about commonly confused words. Just memorize which is which.
Its vs. It’s
It’s is short for it is or it has.
It’s too late.
Its shows possession, like his and her.
These are its footprints.
Their vs. There vs. They’re
There refers to a place.
There is a terrarium in the first building; it is over there.
They’re is a contraction of they are.
They’re not in this building.
Their is the possessive pronoun.
Their house is on the next street.
To vs. Too vs. Two
Two is a number.
There were two books on the table.
Too means «more than enough» and «also.»
After we got our dinner for free, they gave us too much ice cream for dessert, too!»
To indicates direction and action.
We’re going to the…