ACT English: The 15 Grammar Rules That Cover Almost Everything
· 4 min read
ACT English looks like a grammar test and behaves like a pattern-recognition test. The same small set of rules comes back over and over, and once you know them, most questions become quick.
Enhanced ACT English is 50 questions in 35 minutes — about 42 seconds each. Only 40 are scored; 10 are unscored field-test items you cannot identify. The legacy test had 75 questions in 45 minutes.
See which of these rules you actually miss
Knowing the rules and applying them under time are different skills. Real Enhanced ACT-format English questions with an explanation on every miss. About three minutes, no account.
Free · No account needed
The 15 rules
Commas
- Don't separate subject from verb. The student who studied hard passed — no comma before passed.
- Use a comma before a coordinating conjunction joining two independent clauses. She studied, and she passed.
- Set off non-essential information with a pair of commas. My brother, who lives in Ohio, is coming. If removing it still leaves a complete, unchanged meaning, it needs commas.
- Don't use a comma between two items. Only three or more get the series treatment.
Verbs
- Subject-verb agreement. Find the actual subject, not the nearest noun. The box of books is heavy.
- Keep tense consistent unless the sentence signals a shift in time.
Pronouns
- Agreement. A singular noun takes a singular pronoun.
- Clear antecedent. If it could refer to two things, it's wrong.
- Who vs whom — who does the action, whom receives it.
- Its/it's, their/there/they're, your/you're. Apostrophe means a contraction, always.
Structure
- Parallel structure. Running, swimming and biking — not running, swimming and to bike.
- Modifiers go next to what they modify. Walking home, the rain started says the rain was walking.
- No comma splices. Two independent clauses need a period, a semicolon, or a comma plus conjunction.
Style
- Shorter is usually better. The ACT hates redundancy. In my personal opinion is three words too long.
- Transitions must match the logic. However needs a contrast. Therefore needs a cause. Read the sentences either side before choosing.
The single best strategy
Read the entire sentence, not just the underlined part.
Most ACT English errors are audible when you read the full sentence. Students who analyse each option grammatically are slower and no more accurate than students who know the rules and then trust their ear.
Second-best: when two options are both grammatically correct, pick the shorter one — unless it drops information the sentence needed.
The conversion curve is brutal at the top
English has 40 scored questions and the scale steepens sharply near the ceiling. On ACT's published table:
| Raw (of 40) | Scale |
|---|---|
| 40 | 36 |
| 38 | 35 |
| 36 | 31 |
| 35 | 29 |
| 32 | 26 |
| 28 | 22 |
| 24 | 20 |
| 20 | 16 |
Note the jump from 35 to 36 raw: 29 to 31. The scale skips 30 entirely on that form. Near the top, each raw point is worth roughly two scale points — which is why careless errors are so expensive for strong students.
Find out which rules are actually costing you
Real Enhanced ACT-format questions with an explanation on every miss. Most students discover their English problem is two or three rules repeating, not "grammar".
Free · No account needed
Pacing
42 seconds per question. In practice, most take 20 seconds and a few take 90.
Don't read the passage first. Work through it question by question — the underlined portions come in order, and reading ahead wastes time on text no question asks about.
Check the clock at question 25 — you should be around 17 minutes.
What ACT actually reports
Three reporting categories: Conventions of Standard English (the grammar rules above), Knowledge of Language (word choice, style, tone) and Production of Writing (organisation, transitions, purpose).
Most students who think they have "an English problem" have a Conventions problem — usually commas — and can fix it in an afternoon.
Related
Frequently asked questions
How many questions are on ACT English?
50 questions in 35 minutes on the Enhanced ACT, down from 75 questions in 45 minutes on the legacy test. Only 40 are scored — the other 10 are unscored field-test items mixed in unmarked. That works out to about 42 seconds per question.
What grammar is tested on the ACT English section?
A narrow and highly repetitive set: comma use, subject-verb agreement, pronoun agreement and case, apostrophes, verb tense, modifiers, parallel structure, and commonly confused words. ACT groups these as Conventions of Standard English, alongside Knowledge of Language and Production of Writing.
Is the shortest answer usually right on ACT English?
Often, but it is a tiebreaker rather than a rule. The ACT penalises redundancy and wordiness, so when two choices are both grammatically correct the shorter one usually wins. Never pick the shortest option if it introduces an error or removes needed information.
What raw score do I need for a 30 on ACT English?
On ACT's published conversion table, 35 of the 40 scored questions converts to a 29 and 36 converts to a 31 — the scale skips 30 in English on that form. The table is steep at the top: the last few raw points are worth two scale points each.
How do I get faster at ACT English?
Read the full sentence, not just the underlined portion, and trust your ear once you know the rules. Most students are slow because they analyse every option grammatically. Reading the sentence as written usually makes the error audible, which is far quicker.