Punctuation
Commas, semicolons, colons, apostrophes, dashes and end punctuation.
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Punctuation
Commas, semicolons, colons, apostrophes, dashes and end punctuation.
✏️ Commas
Part 1 of 7 — Items in a Series, Introductory Elements, Nonessential Clauses & Coordinate Adjectives
Commas are the most frequently tested punctuation mark on the ACT English section (50 questions in 35 minutes on the enhanced ACT, each with 4 answer choices). Comma questions show up in nearly every passage, so mastering these rules gives you a significant scoring advantage.
The Four Big Comma Rules on the ACT:
| Rule | Example |
|---|---|
| Items in a series | She packed books, snacks, and water. |
| After introductory elements | After the lecture, students asked questions. |
| Around nonessential clauses | My sister, who lives in Chicago, is visiting. |
| Between coordinate adjectives | It was a long, exhausting day. |
Why this matters: The ACT doesn't just test whether you know the rules — it tests whether you can avoid adding commas where they don't belong.
🔗 Semicolons & Colons
Part 2 of 7 — Joining Independent Clauses, Introducing Lists & Semicolons vs. Commas
Semicolons and colons appear on nearly every ACT English section. They look intimidating, but the rules are straightforward once you learn them.
Key Principle: Both semicolons and colons must be preceded by a complete sentence (independent clause). If the words before the mark can't stand alone, the punctuation is wrong.
| Mark | Primary Use | Example |
|---|---|---|
| Semicolon (;) | Joins two related independent clauses | She studied hard; she earned an A. |
| Colon (:) | Introduces a list, explanation, or elaboration | He needed three things: focus, practice, and patience. |
🔤 Apostrophes
Part 3 of 7 — Possessives, Contractions, Its vs. It's & Plural Possessives
Apostrophe questions appear on virtually every ACT English section. They test two things: possession and contractions. The ACT's favorite trick is confusing possessive pronouns (which never use apostrophes) with contractions (which always do).
Two Jobs for Apostrophes:
| Job | Rule | Example |
|---|---|---|
| Possession | Add 's or ' | the dog's bone, the dogs' bones |
| Contraction | Replace missing letters | don't = do not, it's = it is |
Critical Rule: Possessive pronouns — its, their, your, whose — NEVER take apostrophes.
— Dashes & Parentheses
Part 4 of 7 — Em Dashes for Emphasis, Parenthetical Asides & When to Use Which
Dashes and parentheses both set off extra information in a sentence, but they create different effects. The ACT tests whether you know the rules for each — and whether you can keep them consistent.
The Big Three Tools for Setting Off Information:
| Tool | Effect | Example |
|---|---|---|
| Commas | Neutral, most common | My cousin, a doctor, helped. |
| Parentheses | De-emphasize / aside | My cousin (a doctor) helped. |
| Em dashes | Emphasize / dramatic pause | My cousin — a doctor — helped. |
Critical ACT Rule: When you use two dashes or two commas or two parentheses to set off information, you must use the same mark on both sides. You cannot mix them.
- ❌ The results — which surprised everyone, were published Friday.
- ✅ The results — which surprised everyone — were published Friday.
📌 End Punctuation & Quotation Marks
Part 5 of 7 — Periods with Quotes, Question Marks & Exclamation Points
End punctuation and quotation marks don't appear as often on the ACT as commas, but when they do, the rules are strict. Getting these right is easy — once you know the conventions.
The Basics:
| Mark | Use |
|---|---|
| Period (.) | End a declarative or imperative sentence |
| Question mark (?) | End a direct question |
| Exclamation point (!) | End an exclamatory sentence (rare on the ACT) |
ACT Approach: The ACT strongly prefers a neutral, academic tone. This means periods are almost always preferred over exclamation points. If an answer choice uses an exclamation point, it's usually wrong.
⚠️ Common ACT Punctuation Traps
Part 6 of 7 — Unnecessary Commas, Comma Splices & Run-On Sentences
The ACT isn't just testing whether you know where to put punctuation — it's also testing whether you know where to leave it out. Many of the trickiest ACT questions involve punctuation that seems right but is actually wrong.
The Three Most Common Traps:
| Trap | What It Looks Like |
|---|---|
| Unnecessary comma | A comma separating things that shouldn't be separated |
| Comma splice | Two independent clauses joined by only a comma |
| Run-on sentence | Two independent clauses with no punctuation at all |
Why These Are Tricky: When you read them aloud, they might "sound" okay. The ACT is testing your knowledge of the rules, not your ear.
🏆 Review & Mixed Practice
Part 7 of 7 — Punctuation Rules Cheat Sheet & Mixed ACT-Style Questions
You've now covered every major punctuation rule tested on the ACT English section. This final lesson reviews the key rules and challenges you with mixed-format questions that mimic real ACT passages.
ACT English Punctuation — Master Cheat Sheet:
| Rule | Key Point |
|---|---|
| Commas in a series | Use commas between 3+ items, including before the conjunction |
| Introductory elements | Comma after introductory words, phrases, or clauses |
| Nonessential clauses | Commas on both sides (which → commas; that → no commas) |
| Coordinate adjectives | Comma between adjectives if they pass the swap/and test |
| Semicolons | Join two independent clauses; precede "however"/"therefore" only when it joins two clauses |
| "However" as an interrupter | Mid-clause "however" takes a pair of commas: The team, however, continued. |
| Colons | Follow a complete sentence; introduce a list or explanation |
| Apostrophes | Possessives (dog's) vs. contractions (it's = it is) |
| Possessive pronouns | NEVER use apostrophes (its, their, your, whose) |
| Dashes | Emphasize asides; pairs must match |
| Parentheses | De-emphasize asides; punctuation goes outside |
| Periods & commas with quotes | Always inside quotation marks (American English) |
| Unnecessary commas | Never between subject-verb or verb-object |
| Comma splices | A comma alone can't join two independent clauses |
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