Comma questions make up roughly 25 percent of all punctuation questions on the ACT, which means you will see 3 to 5 of them on every test. The good news is that six rules cover about 95 percent of those questions, and the patterns repeat themselves with remarkable consistency. The most important principle to internalize before learning the rules: if you cannot identify a specific grammatical reason for a comma, it should not be there. The ACT is far more likely to test you on unnecessary commas than on missing ones. Students who scatter commas wherever they "feel" a pause consistently lose points. Commas are not breath marks — they are structural signals that serve precise grammatical functions.
Comma questions make up roughly 25 percent of all punctuation questions on the ACT, which means you will see 3 to 5 of them on every test. The good news is that six rules cover about 95 percent of those questions, and the patterns repeat themselves with remarkable consistency. The most important principle to internalize before learning the rules: if you cannot identify a specific grammatical reason for a comma, it should not be there. The ACT is far more likely to test you on unnecessary commas than on missing ones. Students who scatter commas wherever they "feel" a pause consistently lose points. Commas are not breath marks — they are structural signals that serve precise grammatical functions.
Whenever you have three or more items listed in a row, separate them with commas. This applies whether the items are single words, phrases, or entire clauses.
Single words: The test was long, difficult, and exhausting. Phrases: Students studied in the library, at home, and during lunch. Clauses: She knew what to study, when to take breaks, and how to stay focused.
The ACT has firmly planted its flag in the Oxford comma camp. The Oxford comma is the comma placed before the final conjunction in a list, and on every ACT, the correct answer will include it. This is non-negotiable.
Correct on the ACT: red, white, and blue Always wrong on the ACT: red, white and blue
Why does the Oxford comma matter? Because omitting it can create genuine ambiguity: "I admire my parents, Batman and Wonder Woman" reads as though your parents are Batman and Wonder Woman. The Oxford comma fixes it: "I admire my parents, Batman, and Wonder Woman."
Special situations: With just two items joined by a conjunction, no comma is needed — "bread and butter," not "bread, and butter." When individual items in a list already contain commas, upgrade to semicolons to keep things readable: "The committee included John, the president; Mary, the treasurer; and Bob, the secretary."
In January 1848, a carpenter named James Marshall spotted flakes of gold in the American River near Coloma, California, triggering the largest mass migration in American history. Within two years, roughly 300,000 prospectors had descended on the Sierra Nevada foothills, transforming a sparsely populated territory into a chaotic boomtown frontier. As historians have documented the economic and social upheaval of this era, researchers studying the Gold Rush see it as a turning point that reshaped the American West.
The mining process evolved rapidly as surface deposits were exhausted. Early prospectors relied on simple panning techniques, swirling river sediment in shallow metal dishes to separate gold flakes from gravel. Miners also constructed wooden sluice boxes and rocker cradles to process larger volumes of material. Furthermore, hydraulic mining operations eventually blasted entire hillsides with pressurized water cannons, extracting gold at an industrial scale but devastating the surrounding landscape.
The human cost of the Gold Rush extended far beyond the physical dangers of mining. Despite the promise of instant wealth, most prospectors never struck it rich. Merchants and supply vendors frequently earned more than the miners themselves, selling pickaxes shovels and provisions at vastly inflated prices. These suppliers recognized that the real fortune lay not in the ground but in outfitting the thousands of desperate men who believed it did.
A compound sentence joins two independent clauses — two groups of words that could each stand alone as a complete sentence. When you connect them with a coordinating conjunction, you must place a comma before that conjunction. The seven coordinating conjunctions are remembered by the acronym FANBOYS: For, And, Nor, But, Or, Yet, So.
The formula: Independent Clause + comma + FANBOYS + Independent Clause
She studied hard, and she passed the test. The questions seemed easy, but they required careful analysis.
The period test: Replace the comma and conjunction with a period. Can both sides stand alone as sentences? If yes, you need the comma. "She studied hard. She passed the test." — both work, so the compound version needs a comma before "and."
Here is where the ACT tricks you: when the second part shares the subject with the first part, it is NOT an independent clause, and you do not use a comma:
Correct: The test was difficult but rewarding. ("rewarding" has no subject — no comma) Wrong: The test was difficult, but rewarding.
More shared-subject examples (no comma): - She studied all night and passed the test. - The team won the game but lost the championship. - He read the question carefully and selected the best answer.
Also watch for the comma splice — two independent clauses joined with only a comma and no conjunction. This is always wrong: Wrong: The test was hard, students struggled. Right: The test was hard, so students struggled. / The test was hard; students struggled. / The test was hard. Students struggled.
Semicolons and colons are the most predictable punctuation marks on the ACT. While commas have dozens of rules and edge cases, semicolons and colons follow just a handful of patterns that repeat on every single test. They show up in roughly 4 questions per exam, making up about 35 percent of all punctuation questions. Once you learn the rules — there are really only four — these questions become automatic. The key insight is that both marks share a common requirement: a complete, independent clause must appear before them. If you remember nothing else from this chapter, remember that.
A semicolon joins two independent clauses — two groups of words that could each stand alone as complete sentences. Think of a semicolon as having the same "weight" as a period: anywhere you could place a period, you could also place a semicolon. The only difference is that the semicolon signals to the reader that the two thoughts are closely related and belong together.
The golden rule: every semicolon must have an independent clause on both sides. If either side cannot function as a standalone sentence, the semicolon is wrong. No exceptions.
The cover-up test: Cover the left side — is the right side a complete sentence? Then cover the right side — is the left side a complete sentence? If both are yes, the semicolon is correct. This takes five seconds and eliminates all guesswork.
Correct usage: The library closes at 9 PM; students often study there until closing. She loves classical music; her brother prefers jazz. The experiment failed; the researchers had to start over.
Each example has two complete sentences on either side. They are closely related — the second adds detail, contrast, or consequence.
Incorrect usage: Because it was raining; we stayed inside. — "Because it was raining" is a dependent clause (cannot stand alone). No semicolon allowed. Running through the park; she tripped. — "Running through the park" is a participial phrase, not an independent clause.
Red flag words that create dependent clauses and break semicolons: because, although, though, even though, since, when, whenever, while, if, unless, until, before, after, as, once, wherever, whether. If you spot any of these words near a semicolon, check carefully.
This is one of the ACT's most frequently tested patterns, appearing on nearly every test. When a conjunctive adverb (a transition word like however, therefore, consequently) sits between two independent clauses, the correct punctuation is: semicolon before the transition, comma after it.
Pattern: [Independent clause]; [conjunctive adverb], [independent clause]
I studied hard; however, I still struggled. The road was icy; therefore, we drove slowly. She missed the deadline; consequently, her application was rejected. The hotel was overpriced; furthermore, the service was terrible.
The most common conjunctive adverbs on the ACT: however, therefore, consequently, furthermore, nevertheless, moreover, meanwhile, thus, otherwise, indeed, likewise, instead.
The comma splice trap: Using only commas around a conjunctive adverb between two independent clauses is a comma splice — always wrong. WRONG: I studied hard, however, I failed. RIGHT: I studied hard; however, I failed.
FANBOYS vs. everything else: Coordinating conjunctions (for, and, nor, but, or, yet, so) use a comma before them. Conjunctive adverbs use a semicolon. This single distinction is tested constantly. I was tired, but I kept going. (comma + FANBOYS) I was tired; however, I kept going. (semicolon + conjunctive adverb + comma)
Along the Nagara River in Gifu Prefecture, fishermen still practice ukai, a 1,300-year-old method of catching sweetfish using trained cormorants. Each evening from May through October, master fishermen called usho launch wooden boats onto the dark river, guiding flocks of cormorants by firelight. The birds dive beneath the surface and they snatch fish in their long beaks while snares tied around their throats prevent them from swallowing the larger catches.
The training of a cormorant requires extraordinary patience. Usho raise their birds from hatchlings, feeding them by hand and teaching them to respond to voice commands. A skilled cormorant can work for fifteen to twenty years, and the bond between bird and handler often lasts a lifetime. The Japanese government has recognized this tradition by designating master usho as national cultural treasures.
Modern fishing technology has made ukai commercially obsolete, yet the practice endures for cultural and ecological reasons. The cormorants do not damage riverbeds or leave chemical residue, unlike modern trawling equipment. Tourism has also sustained the tradition, as thousands of spectators gather along the riverbanks each summer to watch the spectacle of flames, birds, and darting fish.
Apostrophes do exactly two things in English: they show possession and they form contractions. That is the entire scope of what the ACT tests with its 2 to 3 apostrophe questions per exam. The test makers dress these questions up in formal academic language, but underneath the complexity, every apostrophe question comes down to one decision — is this showing ownership, or is it replacing missing letters? Once you can answer that question reliably, apostrophes become some of the easiest points on the test.
To show that something belongs to a noun, you add an apostrophe. The exact placement depends on whether the noun is singular or plural.
Singular nouns get apostrophe + s regardless of what letter they end with: The dog's bowl (one dog owns the bowl) Sarah's backpack (Sarah owns the backpack) The boss's office (one boss owns the office) James's book or James' book (both are accepted on the ACT)
Regular plural nouns (ending in -s) get an apostrophe after the s: The dogs' bowls (multiple dogs own bowls) The students' lockers (multiple students) The teachers' lounge (shared by all teachers)
Irregular plural nouns (not ending in -s) get apostrophe + s, just like singulars: The children's playground The women's department The people's choice
The two-step process makes this foolproof: first make the word plural, then add possession. One boy becomes boys, then boys' team. One child becomes children, then children's games. If the plural ends in -s, the apostrophe goes after it. If it does not end in -s, add 's.
Joint vs. separate possession is an additional rule the ACT tests. When two people share one thing, only the last name gets the apostrophe: Tom and Sarah's house (one shared house). When each person owns their own item, both names get apostrophes: Tom's and Sarah's cars (each has a separate car).
Time and money expressions can also be possessive. If you can rephrase with "of," it is possessive and needs an apostrophe: two weeks' notice (notice of two weeks), today's news (news of today), one hour's drive (drive of one hour). But simple duration is not possessive: "It happened two years ago" — no apostrophe needed.
In a contraction, the apostrophe replaces the missing letters when two words are combined: do not becomes don't (the "o" is missing), they are becomes they're (the "a" is missing), would have becomes would've (the "ha" is missing).
The most commonly tested contractions on the ACT involve pronouns paired with verbs: it's (it is), they're (they are), you're (you are), who's (who is). Each of these has a possessive twin that looks similar but uses no apostrophe: its, their, your, whose. The ACT exploits this confusion relentlessly.
The expansion test resolves every contraction question instantly. Replace the word with its expanded form. If the sentence still makes sense, the contraction is correct. If it sounds wrong, you need the possessive form instead.
"The dog wagged its tail." Expand: "The dog wagged it is tail" — nonsense. Use its (possessive). "It's a beautiful day." Expand: "It is a beautiful day" — works. Use it's (contraction).
The deadly error: "would of," "could of," "should of" are always wrong. These sound like the contractions would've, could've, should've when spoken aloud, but "of" is never correct here. If you see "could of" in an answer choice, eliminate it immediately.
Dashes and parentheses serve opposite purposes: dashes amplify information by forcing the reader to stop and pay attention, while parentheses muffle information by tucking it away as an aside. The ACT tests whether you can choose the right one based on how important the information is to the passage. You will see 1 to 2 of these questions per test. The rules are simple — the key is matching the punctuation to the intended emphasis level.
Every piece of information you insert into a sentence carries a certain weight, and your punctuation choice signals that weight to the reader. Think of it as a volume dial:
Em dashes — maximum volume. Dashes create a dramatic pause that forces the reader's attention onto whatever sits between them. They are the neon highlighter of punctuation. The winner — a complete unknown — shocked everyone. The dashes make the surprise impossible to miss.
Commas, neutral volume. Commas provide standard separation without adding or subtracting emphasis. They maintain the natural reading rhythm. The winner, a complete unknown, shocked everyone. Same information, no special drama.
Parentheses (minimum volume). Parentheses signal that the enclosed information is supplementary — helpful but not essential. The reader could almost skip it. The winner (a complete unknown) shocked everyone. The surprise is still there, but it is whispered rather than spotlighted.
No punctuation — fully integrated. The information blends seamlessly into the sentence with no pause at all. The unknown winner shocked everyone.
On the ACT, the question is always: how important is this information to the main point? If it is crucial or dramatic, dashes are correct. If it is standard context, commas work. If it is optional background detail, parentheses are the right call.
Em dashes serve four main purposes on the ACT.
Surprising or dramatic information: The policy — which affects every student on campus — starts Monday. The dashes force the reader to absorb the scope of the impact.
Important clarifications that cannot be missed: The experiment — the largest of its kind — produced groundbreaking results. Dashes ensure the reader registers the scale.
Dramatic interruptions or shifts: She opened the door and saw — nothing. The single dash at the end builds suspense before the anticlimax.
Emphatic lists after a complete thought: Three things matter most — preparation, persistence, and timing. More forceful than a colon, dashes add punch.
Dashes create a slightly informal, conversational tone. They are more common in narrative and journalistic writing than in dry academic prose. Overusing them weakens their impact — one pair per paragraph is usually the maximum before they start to lose their dramatic effect.