These 2 Grammar Mistakes Can RUIN Your ACT English Score

The ACT English section is relatively straightforward. It’s divided into five passages, each with 15 different questions.

Each passage is about the same difficulty level as the others, and the actual questions within the passage are randomized by difficulty. In other words, no passage is any harder than another. And within a passage, there is no rhyme or reason to which questions are easier or harder (unlike the Math section). It’s random. You may get a medium, followed by a few easies, then a hard, then another easy.

What you’re tested on is split between straight-up grammar and rhetorical devices, with grammar questions taking the lead.

In my experience, I've found that there are two main grammar mistakes that can wreak havoc on your score...and I can tell you how to fix them so that they can save it instead.


Mistake #1) Thinking the subject is within a prepositional phrase.

Subject-verb agreement features prominently in the ACT English section. What’s funny about subject-verb agreement is that you’re probably already great at picking the appropriate form of a verb to match the subject.

For example, if I say “the dog bark,” you’d probably cover your ears with your hands and scream. It just SOUNDS wrong. Clearly, when there’s a singular subject (i.e. “the dog”), it needs to be matched with a singular verb, which usually ends with an “s” (i.e. “barks” and not “bark”).

That part’s easy. The hard part is correctly identifying the subject!

There are 6 main ways the ACT can obfuscate (hide) the subject. But the single one that most people fall for, and that occurs most often?

Muddying the waters with a prepositional phrase.

Here's an example of a sentence the ACT might give you:

One of the flowers are orange.

In this sentence, many students will mistakenly think the subject is the word “flowers.” However, if we look closely, the word “flowers” appears in a phrase that starts with “of”—and “of” is a preposition.

The subject is NEVER in a prepositional phrase.

So here’s a trick that works for my students. Just cross out the phrase starting with the preposition, like so:

One of the flowers are orange.

Now, it’s easy to see that the subject is the only noun left: “One”! (By definition, singular.)

Thus, the correct sentence goes like so:

One of the flowers is orange.

The reason this is tricky is that if we rely on our ears, we hear “flowers are” and that seems right. That’s exactly what the ACT wants you to hear, and to think. That’s why they make sure that the noun at the end of the prepositional phrase is opposite in number to the real subject—the one they’re trying to hide. In other words, if the real subject is singular, the noun at the end of the prepositional phrase will likely be plural, and vice versa.

So you have to use a little more logic and identify the subject with your brain, not just your ears.


Mistake #2) Trying to connect two complete clauses with only a comma.

So before we discuss why this is wrong, first, a little recap on what a “clause” is. It’s just a grouping of words that contains both a subject and a verb.

Some clauses can stand on their own. I call these “independent clauses” or “complete clauses.”

Kelly drinks water.

Then again, some can’t. I refer to these as either “dependent clauses” or “incomplete clauses.”

While Kelly drinks water. Nope! This one could NOT be its own sentence.

There are several ways of combining two complete clauses, as well as several ways to combine an independent/complete clause with a dependent/incomplete clause. However, here’s what can NEVER happen, which the ACT loves to try to trick you with:

You CANNOT join a complete clause with another complete clause with only a comma! That mistake, known as a “comma splice,” has its own very special place in Grammar Hell.

Kelly is thirsty, she drinks 2 gallons of water.

No. No! Noooooo. You’ve just created a run-on sentence. Please don’t commit this grammar crime!

So, how do you go about fixing this one? There are several ways, luckily, and the ACT isn’t picky.

A) Make them 2 separate sentences:

Kelly is thirsty. She drinks 2 gallons of water.

B) Combine them with a comma AND a FANBOYS (“For And Nor But Or Yet So”):

Kelly is thirsty, so she drinks 2 gallons of water.

C) Combine them with a semi-colon. DO NOT USE A FANBOYS!

Kelly is thirsty; she drinks 2 gallons of water.

D) Combine them with a colon. This ONLY works if the second clause answers or clarifies a question the first clause prompts.

This doesn’t really work with poor Kelly and her hydration dilemma, but could work with a sentence like this:

She wouldn’t find out until Saturday why she didn’t get the part in the play: she was too tall for the costume.

When we read that, our response after the first sentence is “Oooooh! Tell me! WHY didn’t she get the part?” That’s why we use a colon. The second part answers the question we’re all asking after reading the first complete clause.

Make sense?

These two easy-to-miss grammar problems are tricks the ACT uses over and over again. If you can become a pro at spotting those two mistakes and consistently correcting them, that’s a 5-6 point increase right there. Not a bad reward for learning two little grammar rules.