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Rachel Kapelke-Dale

ACT English Punctuation: Everything You Need to Know

It’s finally here: test day. You open your book when the proctor prompts you, flip to that first page, and…Uh-oh. Time for some English questions. More specifically, time for some ACT English punctuation, grammar, and usage questions.

It can be easy to overlook the English section during your ACT prep. After all, if you live in an Anglophone country, you’ve probably had English lessons for years. However, the ACT tests very particular types of English rules in context. That’s right—just memorizing ’em won’t be enough.

Don’t worry, you can absolutely master these question types with a little practice. But before you do, let’s take a quick overview of ACT English punctuation, one of eight main areas the ACT focuses on. After all, there are tons of punctuation marks that the ACT could test…but there are very few that it actually does!

So here it is—everything you need to know about ACT English punctuation!

If you want to jump right to a particular topic, here’s a handy Table of Contents.



The rules governing commas can be tricky; often, there’s some flexibility for your personal style. For the ACT, the “style” rules either have one “right” answer or are just not tested.

So, for our purposes here, it’s easiest to think of commas as separators: they point out information that, for whatever reason, needs to be set apart from the rest of the sentence. Here are some examples to show you what I mean.


Here, the commas are separating the individual items in a list of three or more items:

Othello didn’t realize that Iago was conniving, two-faced, and evil.

See those commas there? They’re pointing out all of Iago’s finer qualities, of which Othello is unaware. We have to use commas to separate them or the end of the sentence would be a bit of a mushy mess.

(Note: the comma before the “and” is called the “Oxford comma.” In real life, the Oxford comma is largely a matter of style, but it can make certain sentences clearer. On the ACT, always include the Oxford comma in lists. It’s unlikely that an Oxford comma will be the only difference between two answer choices, but the ACT prefers it. So, as far as the test is concerned, so should you!)


Use a comma to separate two adjectives when the word “and” could be inserted between them.

Romeo’s choice to take poison was a rash, foolish decision.

(It was a rash and foolish decision. The comma is necessary.)

Hamlet was a sad young man.

(Hamlet was a sad and young man? No, that sounds odd. Don’t use a comma here.)

Additional (Parenthetical) Information

Let’s say I’m telling you a story about a guy named James. Here’s my beginning:

James is rather fond of “Slim Jims.”

A simple enough sentence, no? But it leaves us with a major unanswered question: who is James? Clearly, he must be someone I know, or I wouldn’t be able to discuss his dietary preferences, but I haven’t told you who he is or how I know him.

Well, James is my cousin. I know he likes “Slim Jims” because we’re family. I need to put that information into the sentence to satisfy my readers’ burning curiosity about James. I could rephrase it to say:

My cousin James is rather fond of ‘Slim Jims.”

And it would be 100% grammatical, or I could do this:

James, my cousin, is rather fond of “Slim Jim’s.”

The difference here is one of style, and neither one is “more right” than the other. However, if I’m going to include the information that James is my cousin after I introduce his name, I need to separate it in commas.

The two-commas rule works in many cases. If the extra information isn’t grammatically necessary to the sentence, you can separate it with two—only and always two—commas. (You can also use dashes or parentheses for a similar effect. Again, it’s a style thing, and differences in style won’t be tested on the ACT.)

Here’s another example:

James is rather fond of “Slim Jims.” My aunt, however, would rather starve than eat them.

The sentence would be perfectly understandable without the word “however,” but I wanted to include it anyway. It’s additional information, a non-essential word. Therefore, I separate it with two commas.


This point is closely related to the last one. If you’re starting a sentence with a transition or other introductory word or phrase, separate it from the rest of the sentence with a comma.

In my life, I’ve made many mistakes. Very few of them were grammatical.


In case you don’t remember or were never taught, here’s a quick run-down on clauses, phrases, and the differences between the two.

Don’t worry, it’s mostly painless.

Phrases are groups of related words that don’t have a subject or verb.

(Examples: “over the rainbow,” “singing in the rain,” “a tale as old as time,” etc.)

Clauses are groups of related words that do have a subject and verb. They come in two types.

Independent clauses are complete sentences.

(Examples: “I think I’ll try defying gravity,” “The sun’ll come out tomorrow, etc.)

Dependent clauses have a subject and verb, but are not complete sentences.

(Examples: “under the sea,” “if I only had a brain,” etc.)

Independent—Dependent Clauses

You can use commas to separate independent clauses from dependent clauses. Usually, a dependent clause will have a subordinating conjunction at the beginning. Sadly, there are too many subordinating conjunctions to list them all, but here are some of the most common ones:

until, if, since, because, although, once, as, when, where, why, before, than, that, though, unless

If you see these words (or similar ones) at the beginning of a clause, that clause is dependent and needs an independent clause to be a complete sentence. An example for you (and bonus points if you can name that musical):

Once I’m with the Wizard, my whole life will change.

(dependent clause) (independent clause)

The word “once” in this sentence is the subordinating conjunction. The clause that has the word “once” in it is the dependent clause, so it leans on the other half to make one complete, grammatically correct sentence.

Independent—Independent Clauses

In one and only one situation, you can use a comma to separate two independent clauses. This is only permissible if you have a coordinating conjunction immediately following the comma.

If I just made your brain seize up with the grammatical jargon there, don’t worry! I have a nifty mnemonic for you. A coordinating conjunction is one of your FANBOYS:








You can use a comma and one of your FANBOYS to separate two complete sentences.

Important: Make sure you’re using the right FANBOYS for your situation, and you will never ever need more than one in a row. (I’m looking at you, students who use “but yet” in sentences! One or the other will do!)

Here are a few examples:

Most students find grammar dull, so I try to spice it up a bit with silly pop culture references.

I always enjoyed grammar, but I understand why some people might not.

Did you want to continue talking about commas, or should we discuss something else?


The comma splice is a very common error that, once you learn about it, will spoil your ability to read or write comments on the Internet. I’m very sorry to have to do that to you, but it’s for the good of your ACT score.

Here is an example of a comma splice:

It is physically painful for me to write this sentence, I hope you appreciate it.

See what I did there? I tried to separate two independent clauses with just a comma. Technically, that example is a run-on sentence because I didn’t separate the two clauses properly (either with a period, a semicolon, or a comma and an appropriate FANBOYS conjunction). Because it’s a very common error, it looks and sounds right to many students, which is why the ACT loves to test it. Let’s look at an ACT-style example.

Garret and Declan went to the supermarket, they wanted to buy some orange juice.

B. supermarket they wanted
C. supermarket. They wanted
D. supermarket they. Wanted

Our answer would be C, because it’s the only answer choice that properly separates the two clauses in the example. A is our comma splice (which is always, always wrong), B actually makes it worse by removing any separator at all, and D turns a run-on sentence into a nonsensical sentence and a fragment.



The colon ( : ) is a fairly straightforward punctuation mark. The rules for colon usage are clear-cut and don’t leave much room for error. Master these, and the day is yours!

Colons are used after independent clauses (a.k.a. “complete sentences”) in four situations. You can remember them by remembering the letters LEQ.


No, it doesn’t mean “for the way you look at me,” like in one of my favorite songs. Here, the L stands for list. You use a colon after an independent clause to introduce a series of items.

I have three things on my to-do list for this summer: sitting, loafing, and goofing off.


The E stands for explanation. You can use a colon after a complete sentence to expand on what you’re talking about.

This I know: Do or do not. There is no ‘try.’ – Yoda, The Empire Strikes Back

While I was in Ireland, I had heaven in a cup: a Cadbury “Flake” bar in vanilla ice cream.


The Q stands for quote. You can use a colon to introduce a quotation.

Well, it’s like Ralph Waldo Emerson once said: “I hate quotations.”



Semicolons are great. They’re my favorite punctuation mark—no, seriously. They’re sophisticated; use them properly, and people will be impressed at your mastery of the English language.

Here are the rules for semicolons:

  • Use a semicolon to separate two closely related independent When I say “closely related,” I mean that they clearly belong as part of the same thought. The two sentences are grammatically complete, but make much more sense when joined together.

With educated people, I suppose, punctuation is a matter of rule; with me it is a matter of feeling. But I must say I have a great respect for the semi-colon; it’s a useful little chap. Abraham Lincoln

  • Use a semicolon to separate items in a list that already contains commas. In this example, the narrator is meeting with three people. If I hadn’t used semicolons, you might think the narrator was meeting five people.

I have a meeting with Donna Jones, the school principal; Ms. Hawkins, my daughter’s English teacher; and Jim Jackman, the volleyball coach.

Unclear version: I have a meeting with Donna Jones, the school principal, Ms. Hawkins, my daughter’s English teacher, and Jim Jackman, the volleyball coach.



Before we start talking about this, we need some clarity of language. A hyphen ( – ) is often used to join words together. We’ll talk about those later in this section. A dash ( — ) is a versatile and often dramatic punctuation mark, and since it’s more fun to talk about, we’ll discuss it first.

There are actually two different kinds of dashes. The en dash, which is slightly shorter, and the em dash, which is the one you can see in the previous paragraph. The good news is that the ACT isn’t going to test you on the differences between the two. You will only be tested on the rules of the em dash, which is what we’ll cover here.

There are three major uses for the em dash, and they’re fairly straightforward.

  • Use an em dash to show a change in flow in the middle of a sentence. Here, a pair of em dashes set off additional information in the same way commas or parentheses would.
    Critics of the Pokémon video game franchisealso known as people who have no funsay that each game in the series feels exactly the same.
    (Note: The difference here is style only, so you won’t have a question on the ACT that will ask you to choose from among dashes, commas, or parentheses. You may be asked to make sure that they are used in pairs or that the additional information really needs to be separated from the rest of the sentence.)
  • Use an em dash to introduce an explanation in the same way you would use a colon. Remember: always make sure you have an independent clause before the colon or em dash!
    I’m not a big fan of Skyrim—if I can’t figure out where the story is going in the first hour, then I don’t want to play the game!
  • Use an em dash to indicate a change in thought or a humorous or dramatic addition to the sentence.
    Pac-Man, at its core, is a game about consuming food pellets and pieces of fruit while trying to outrun beings who are out to destroy yousounds like a typical day in high school to me!


Wait! What About Hyphens?

Oh. Right. I promised you we’d talk about those.

Well, to be honest, the ACT isn’t really going to test you much on hyphen usage. You should know the rules anyway, just in case it comes up, but it’s not one of their favorite topics.

  • Use a hyphen to join two or more adjectives together when they act as a single idea and come before the noun they modify
    a 5-page paper
    a one-year-old girl
    an all-too-common mistake
    a friendly-looking dog (remember, even though it ends in -ly, “friendly” is an adjective!)
  • Don’t use a hyphen when you have an adjective and an adverb before a noun. Adverbs can’t modify nouns, so it’s already clear without the hyphen.
    Katie was terribly tired.
    Danny was really generous.
  • Use a hyphen for all spelled-out numbers from twenty-one to ninety-nine and fractions.
    one-third of high school students
    seventy-six trombones
  • Use a hyphen for most compound last names.
    Lady Guinivere Hopkins-Drake will attend the soirée.
  • Use a hyphen for some compound nouns.



Let’s turn to Kristin for an overview of apostrophe usage on the ACT.


The ACT English test loves to test all sorts of punctuation, but especially apostrophes. Check out the video for everything you need to know about grammar rules for apostrophes on the test. Here’s the gist:

Apostrophes are used for two different purposes:

To show possession: Mary’s books.
For contractions: would not → wouldn’t.

Most of the apostrophe questions on the test will have to do with the first case: possession and also a few special cases that people always mess up (I’m looking at you, it’s its.)

Singular Possessive

If a singular noun is “possessing” something, the apostrophe goes before the “s”. For example, the dog’s bone, the ventriloquist’s puppets. Remember that a collective noun, such as “team” or “company”, even though they might be made up of people are singular. So if one team has a bus, it’s the “team’s bus.”

Plural Possessive

…but if multiple teams share a bus, it’s the “teams’ bus.” This is because for plural nouns, the apostrophe comes after the “s”. So “the girls’ jackets” let’s us know we are talking about multiple girls with multiple jackets, not one girl with an envious boatload of jackets (that would be “girl’s jackets”).

The Exceptions to the Apostrophe Rule

I’m grouping in these commonly confused words with this little lesson on apostrophes because they include apostrophes, and well, lots of times when you see apostrophes on the ACT, it’s really about these commonly confused words. And they are commonly confused because they are exceptions to the rule about using apostrophes to show possession. When you are dealing with the pronouns its, whose, and your, these pronouns actually already show possession. And their sneaky shadow doubles with the apostrophes are actually contractions.

Here’s a refresher:

Its vs it’s
Its = the possessive pronoun
It’s = it is

Whose vs who’s
Whose = possessive pronoun
Who’s = who is

Your vs. you’re
Your = possessive pronoun
You’re = you are

If you are ever not sure which one to choose, try reading in the full expression for the contraction into the sentence and see if it makes sense. Let’s say you see: “The dancing skeleton picked up it’s scattered bones.” Does “The dancing skeleton picked up it is scattered bones” make sense? No, so the answer is “its”, not “it’s”.

ACT English Punctuation Wrap-Up

What’s one of the biggest mistakes students can make on the ACT English section? Choosing something because it “sounds good.” There are a lot of trap answers out there that sound good.

Luckily, with English punctuation, it’s hard to “hear” the right answers. Still, rather than just memorizing the rules or relying on your ear, you can use the info in this post to best advantage by making flashcards with the sample sentences (without punctuation!) on them, and the correct punctuation—with explanations—on the back.

Remember, it’s all about context! And the more punctuation you see in context, the better you’ll do on the ACT.

Thank you to Magoosh ACT Blogger Catrina Coffey and ACT expert, Magoosh Senior Manager, and all-around superhero Kristin Fracchia for contributing content and expertise to this ACT English punctuation guide!

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About Rachel Kapelke-Dale

Rachel is a High School and Graduate Exams blogger at Magoosh. She has a Bachelor of Arts from Brown University, an MA from the Université de Paris VII, and a PhD from University College London. She has taught test preparation and consulted on admissions practices for over eight years. Currently, Rachel divides her time between the US and London. Follow Rachel on Twitter, or learn more about her writing here!

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