ACT English Study Guide

ACT describes the English section as putting you in the position of a writer who makes decisions to revise and edit a text. ACT writes the passages in-house, in a range of genres, and the questions sit alongside the text. You are judged not on what you understood, but on whether you can make a sentence, paragraph or essay work better.

What the Questions Look Like

• Underlined or highlighted portions with alternatives, many including NO CHANGE.
• Boxed numbers or bracketed asterisks, which mark questions about a section of the passage rather than an underlined part.
• Whole-passage questions, placed at the end of a passage.
• NOT or LEAST questions: three choices work; you are hunting for the one that fails.

The Question Stem Now Tells You the Skill

In ACT's 2025/2026 Practice Test 1, the 50 questions span six passages, and most stems name the skill being tested:

Stem wording	What it is testing
"Which choice makes the sentence most grammatically acceptable?"	Punctuation, sentence structure or usage
"Which choice is least redundant in context?"	Concision
"Which choice is clearest and most precise in context?"	Word choice
"Which choice most effectively maintains the essay's tone?" or "stylistic pattern"	Style and tone
"Which transition word or phrase is most logical in context?"	Logical connection between ideas
"The writer is considering adding (or deleting)..."	Relevance and focus
"The writer wants to emphasize..." or "Given that all the choices are accurate..."	Meeting a stated goal
"The best placement for the underlined portion would be..."	Organization

When a stem says "Given that all the choices are accurate," grammar is not the issue. Every option is correct English; only one does the job the stem describes.

The Three Reporting Categories

Category	Share of section	Practice Test 1 (scored items)	What it covers
Production of Writing	38 to 43%	15 of 40	Topic development (purpose, goals, relevance) and organization, unity and cohesion (order, transitions, introductions and conclusions)
Knowledge of Language	18 to 23%	8 of 40	Precise and concise word choice; consistent style and tone
Conventions of Standard English	38 to 43%	17 of 40	Sentence structure and formation, punctuation, usage

Grammar and punctuation are under half the scored test. Production of Writing is just as big, and it rewards reading the paragraph, not just the sentence.

Why Every Error Matters

In the conversion table for ACT's 2025/2026 Practice Test 1, 40 correct converts to 36, 38 correct to 35, 36 correct to 31 and 34 correct to 28. Tables vary by form, but near the top a single missed question can cost one or two scale points.

Punctuation questions are the easiest to spot: the answer choices are the same words with the punctuation moved. Learn the rules below and you can usually eliminate two choices in seconds.

1. Joining Two Independent Clauses

An independent clause has a subject and a verb and can stand alone as a sentence. Two of them can be joined in only a few ways:

• A period: The bus was late. We walked.
• A semicolon: The bus was late; we walked.
• A comma plus a coordinating conjunction (for, and, nor, but, or, yet, so): The bus was late, so we walked.
• A colon, when the second clause explains or completes the first: We had one option: we walked.

A comma alone between two independent clauses is a comma splice. No punctuation at all is a fused sentence. Both are always wrong on the ACT. Because a period, a semicolon and a comma with FANBOYS are interchangeable here, a NOT question often lists all three plus one splice.

2. Semicolons and Colons

• A semicolon needs a complete sentence on both sides.
• A colon needs a complete sentence before it; what follows explains or lists. Never put one directly after a verb: The kit includes: tape, glue is wrong.

3. Nonessential Elements

Information that can be lifted out without changing the core meaning is nonessential. It is set off by a matching pair of commas, a matching pair of dashes, or parentheses. Do not mix them: start with a comma, end with a comma.

• Nonessential: My sister, who lives in Denver, is visiting.
• Essential: Students who finish early may leave. (It tells you which students.)

4. Commas You Should Not Add

Many wrong answers add a single comma between a subject and its verb (The old map in the hallway, shows the river), between a verb and its object, directly after "such as," or before an essential identifier (the novelist Toni Morrison takes no commas).

5. Apostrophes

• Singular possessive: the dog's bowl. Plural possessive: the dogs' bowls. Irregular plural: the children's books.
• Possessive pronouns never take apostrophes: its, whose, theirs, yours. It's means "it is" and who's means "who is."
• Plain plurals take no apostrophe: three photos, not three photo's.

Worked Example: A Punctuation Question

The engineers tested the new valve for six [weeks, it] failed only once.

1. What changes across the choices? Only the punctuation between "weeks" and "it." This is a clause-joining question.
2. Check each side. "The engineers tested the new valve for six weeks" is independent. "It failed only once" is independent.
3. Apply the rule. A comma alone is a splice, so NO CHANGE is out. Acceptable fixes: weeks; it, weeks. It, or weeks, and it.

Fragments

A sentence needs a subject and a main verb and cannot be only a dependent clause. Because the rain stopped. is a fragment, and so is The team practicing every day, because an "-ing" verb needs a helping verb.

Modifier Placement

An opening descriptive phrase must describe the noun right after the comma. Hidden under the stairs, Lena found the old trunk says Lena was hidden; Lena found the old trunk hidden under the stairs fixes it.

Parallelism

Items in a list or comparison must share a grammatical form. She likes hiking, swimming and to read breaks the pattern; hiking, swimming and reading keeps it.

Subject and Verb Agreement

Find the true subject by crossing out everything between it and the verb.

• The box of old letters [is / are] in the attic. Cross out "of old letters": The box is.
• Each of the runners [has / have] a number. "Each" is singular: has.
• When the subject follows the verb, flip the sentence: On the shelf sit three trophies becomes three trophies sit.

Verb Tense and Form

Keep tense consistent with the surrounding sentences unless the timeline changes. Use the past perfect (had finished) for an action completed before another past action, and watch irregular forms: had gone, not had went.

Pronouns

• Agreement: a pronoun must match its antecedent in number. The company changed its logo, not their logo, when one company is meant.
• Clear reference: if "it" or "they" could refer to two different nouns, choose the option that names the noun.
• Case: subject forms (I, she, we, who) as subjects, object forms (me, her, us, whom) after verbs and prepositions. Drop the other person to test: Jordan and I left.

Usage Odds and Ends

• Comparisons: "-er" for two things, "-est" for three or more; compare like with like (higher than her brother's).
• Adverbs modify verbs: She ran quickly, not quick.
• Confused words: than and then, affect and effect, fewer (countable) and less (uncountable).

Concision and Redundancy

"Least redundant" questions are among the fastest on the test. Look for a word that repeats an idea already in the sentence.

• At 6 a.m. in the morning: "a.m." already means morning.
• The final outcome, past history: each pair says one thing twice.

The Shortest Answer Rule, With Limits

When all four choices are grammatical and mean the same thing, the shortest is very often best. It is wrong if it drops needed meaning or if the stem asks for something specific, such as emphasis. "Delete the underlined portion" is a real option; check that the sentence still works without it.

Precision

"Clearest and most precise" questions reward specific words over vague ones. The storm did a lot of things to the coast is vague; The storm eroded the coast is precise.

Style and Tone

Match the essay's register: in a formal passage, slang such as a ton of is wrong. If the stem asks you to "maintain the stylistic pattern," copy the structure of the sentences just before.

Worked Example: Concision

Volunteers planted 200 trees along the river, and [the reason why they did this was because] the banks were eroding.

• NO CHANGE: "the reason why... was because" is triple redundancy.
• they did so because: clear, grammatical and short. Correct.
• the reason was due to the fact that: wordy and still awkward.
• because of the reason that: redundant and ungrammatical after "and."

Transitions

Before you look at the choices, decide the relationship between the two ideas. Then pick the word that names it.

Relationship	Typical transitions
Contrast	however, nevertheless, still, yet, on the other hand, in contrast
Cause and effect	therefore, thus, as a result, consequently
Addition	moreover, furthermore, in addition, also
Example	for example, for instance
Similarity	similarly, likewise
Time	then, later, meanwhile, afterward
Emphasis or clarification	in fact, indeed, in other words

If two choices come from the same row, such as "Therefore" and "Thus," neither can be the single correct answer. A stem that says "if any" signals that no transition at all could be best.

Add or Delete Questions

These come in two steps: yes or no, then a reason. Decide yes or no by asking whether the sentence supports the paragraph's main point, then pick the reason that accurately describes the sentence. The usual trap is the right verdict with the wrong reason.

Meeting the Writer's Goal

Stems like "The writer wants to emphasize..." are precise instructions. Underline the goal and choose the option that does exactly that, nothing broader.

Order and Placement

Look for words that need an earlier reference ("this method," "the second trial," "she") and time words ("later," "by then"). Place a sentence where its opening connects to the end of the sentence before it.

Whole-Passage Purpose Questions

"Suppose the writer's purpose had been to... Would this essay accomplish that purpose?" Answer from the passage's actual focus. An essay about one inventor's career does not survey the history of an industry, however many machines it mentions.

Worked Example: A Transition Question

Snow leopards are rarely seen in the wild. [Consequently,] researchers rely on remote cameras to study them.

1. Name the relationship. The animals are hard to see, and that causes researchers to use cameras. Cause and effect.
2. Check the original. "Consequently" signals cause and effect. NO CHANGE fits.
3. Rule out the rest. "However" signals contrast, "Similarly" signals comparison, "For example" signals an example. None fits.

The answer is NO CHANGE, which is a good reminder that the original is often correct.

When to Choose NO CHANGE

ACT's recommended method is to decide how the underlined portion should be phrased, choose NO CHANGE if the original is best, and otherwise look for your version among the choices. Turn that into a routine:

1. Read the whole sentence first, and the next one if the question involves tense, pronouns or a transition.
2. Ask whether the original breaks a rule you can name. If you cannot name an error, do not assume there is one.
3. Compare the choices to see what changes: punctuation, a verb, a word, or length. That tells you the skill being tested.
4. Eliminate any choice with an error, including choices that fix the original error but introduce a new one.
5. If only NO CHANGE survives, pick it with confidence.
6. Reread the sentence with your choice in place.

Pacing 50 Questions in 35 Minutes

That is about 42 seconds per question, or just under six minutes for each of the six passages in ACT's Practice Test 1. Grammar and concision questions should take 15 to 30 seconds; spend the saved time on add or delete, placement and whole-passage questions. If a question is taking too long, guess, flag it and move on: there is no penalty for guessing.