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ACT Punctuation

Every punctuation rule ACT English tests — commas, semicolons, colons, dashes, apostrophes, question marks and when to use no punctuation — with ✓/✗ examples and an ACT-style quiz.

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Punctuation is the largest single group of rules in the Conventions of Standard English category, and it is the easiest place to gain points quickly: the rules are fixed and the same traps appear on every test. This page teaches every punctuation mark ACT English uses, with ✓/✗ pairs, then shows worked items and a quiz in real test format.

What this question type tests

Conventions of Standard English is 38–43% of the 40 scored English questions — about 15–17 questions — and punctuation makes up a large part of it. A punctuation question looks like every other ACT English question: a portion of the essay is underlined, and you choose from four versions that differ only in their punctuation. Usually there is no written question, only the choices, with NO CHANGE first.

When you scan the choices and see that only the punctuation changes, ask two questions:

What is on each side of the mark? A complete sentence (independent clause), an incomplete part, an extra-information phrase, a list item?
Which mark is allowed between those two things? Use the tables on this page.

The one test you will use most

To decide if a part is a complete sentence (independent clause), cover everything else and ask: does it have a subject and a verb, and can it stand alone as a sentence? "The answer is simple" → yes. "Such as fans and lamps" → no. "Which my grandfather built" → no.

1. Commas: the six correct uses

Use	Rule	✓ Correct
A. Two complete sentences + FANBOYS	Comma before for, and, nor, but, or, yet, so when it joins two complete sentences.	The bus was late, so we walked to school.
B. After an introductory part	Comma after an opening word, phrase or clause that comes before the main sentence.	After the storm, the streets were quiet. / However, the plan failed.
C. Extra information (a pair)	Non-essential words in the middle of a sentence go between two commas.	My uncle, who lives in Tanta, grows mangoes.
D. Extra information at the end	One comma before non-essential words at the end.	We visited Luxor, a city full of temples.
E. Lists of three or more	Commas between the items; a comma before the final "and" is acceptable.	She packed bread, cheese, and olives.
F. Equal adjectives	Comma between two adjectives that each describe the noun (you could say "and" between them).	It was a long, tiring journey. (✓ long and tiring)

Essential or extra? This is the most tested comma idea. Remove the words: if the sentence still identifies the same person or thing and keeps its main meaning, the words are extra → use commas. If removing them changes which person or thing you mean, they are essential → no commas.

✓ Students who finish early may leave. (Essential: only those students may leave → no commas.)
✗ Students, who finish early, may leave. (This now says all students finish early.)
✓ My brother, Omar, studies in Alexandria. (If I have one brother, his name is extra → commas.)
✓ The novelist Naguib Mahfouz won the Nobel Prize. (The name tells us which novelist → essential → no commas.)
✓ "which" with commas for extra information; "that" with no commas for essential information: The car that I bought is blue. / My car, which is blue, is old.

2. Commas: the misuses the test loves

Most wrong answers on ACT punctuation contain an extra comma somewhere it is not allowed. Learn these "no comma" places:

Never put a comma…	✗ Wrong	✓ Right
between a subject and its verb (even a long subject)	The students in the back row, laughed.	The students in the back row laughed.
between a verb and its object or complement	The flood covered, many villages.	The flood covered many villages.
to join two complete sentences on its own (comma splice)	The road was closed, we walked.	The road was closed, so we walked. / The road was closed; we walked.
between two verbs that share one subject	She opened the door, and walked in.	She opened the door and walked in.
after "and" or "but" in a list or a join	bread, cheese, and, olives	bread, cheese, and olives
after such as / including / like	items such as, fans and lamps	items such as fans and lamps
between an adjective and its noun	a long, tiring, journey	a long, tiring journey
before or after an essential name or phrase	The novelist, Naguib Mahfouz, wrote it. (if you mean which novelist)	The novelist Naguib Mahfouz wrote it.
only once around extra information (half a pair)	My uncle, who lives in Tanta grows mangoes.	My uncle, who lives in Tanta, grows mangoes.

القاعدة الذهبية للفاصلة

ممنوع تحط فاصلة واحدة بين الفاعل والفعل، ولا بين الفعل والمفعول، حتى لو الفاعل طويل جدًا. والمعلومة الزيادة اللي في نص الجملة لازم تتقفل بنفس العلامة اللي اتفتحت بيها: فاصلة… فاصلة، أو شرطة… شرطة.

3. Semicolons

A semicolon (;) works like a soft period. Its main job is to join two complete sentences that are closely related. The test is simple: if you could put a period there, you can usually put a semicolon there.

✓ The library closes at six; the reading room closes at five.
✓ The road was flooded; therefore, the buses stopped. (A semicolon before a transition word such as however, therefore, moreover, which joins two complete sentences, with a comma after the transition.)
✗ The road was flooded, therefore, the buses stopped. (Comma splice: a transition word is not a FANBOYS conjunction.)
✗ Because the road was flooded; the buses stopped. ("Because the road was flooded" is not a complete sentence.)
✗ She bought three things; bread, cheese and olives. (A list after a complete sentence needs a colon, not a semicolon.)

SAT/ACT extra rule: semicolons in a complex list

On the SAT and the ACT there is one more use. When the items in a list already contain commas, separate the items with semicolons so the reader can see where each item ends.
✓ The team visited Kom Ombo, where many families had resettled; Aswan, the city closest to the old villages; and Cairo, the capital.
✗ The team visited Kom Ombo, where many families had resettled, Aswan, the city closest to the old villages, and Cairo, the capital.
Note the semicolon before the final "and". Use this rule only for lists whose items already contain commas.

4. Colons

A colon (:) comes after a complete sentence and introduces something that the sentence points to: a list, an explanation, emphasis or extra information. Before the colon you must have a complete sentence; after it you may have a word, a list, a phrase or another complete sentence.

Use	✓ Example
List	She packed three things: bread, cheese and olives.
Explanation	The answer was simple: every tool would be checked.
Emphasis	There was only one thing he feared: silence.
Extra information	The project began with one question: how much of the music survived?

✗ The ingredients are: flour, water and salt. ("The ingredients are" is not complete — the colon cuts the verb from its complement.)
✗ We need things such as: tape, glue and wire. (Never after such as / including.)
✓ We need three things: tape, glue and wire.

5. Dashes

A pair of dashes = extra information, exactly like a pair of commas or brackets. The pair must match: dash … dash. ✓ Our teacher — who once rebuilt a radio — will lead the club. ✗ Our teacher — who once rebuilt a radio, will lead the club.
A single dash = emphasis or an interruption, usually near the end of a sentence. ✓ He had trained for one moment — the final lap. ✓ "I think we should —" she began, but the bell rang.
The part of the sentence outside the dashes must still be a complete, correct sentence when you remove what is inside them.

Commas, dashes, brackets: matching rule

For extra information in the middle of a sentence you may use (, … ,) or (— … —) or ( ( … ) ). All three are correct. What is never correct is mixing them: (, … —) or (— … ,). When the choices mix marks, choose the matching pair.

6. Apostrophes

Situation	Rule	✓ Example
One owner	noun + 's	the station's design, the child's bag
Several owners ending in -s	noun + '	the singers' voices, the students' results
Plural not ending in -s	noun + 's	the children's room, the women's team
Simple plural (no owning)	no apostrophe	Many stations were built. ✗ Many station's were built.
its / it's	its = belonging to it; it's = it is / it has	The tree lost its leaves. It's raining.
their / they're / there	their = belonging to them; they're = they are; there = place	They're proud of their station over there.
whose / who's	whose = belonging to whom; who's = who is / who has	The boy whose bike was stolen… / Who's coming?

Test for its/it's and the others: expand the contraction. If "it is" or "they are" makes sense in the sentence, use the apostrophe form; if not, use the possessive.

7. Question marks

Direct question → question mark: ✓ How much of the music survived?
Indirect (reported) question → period: ✓ Some parents asked whether the club is safe. ✗ Some parents asked whether the club is safe?
Words such as asked whether, wondered if, want to know how are signals of an indirect question.

8. When NO punctuation is correct

Many students believe that a long sentence needs commas. It does not. On ACT English, the correct answer is often the choice with no punctuation at all. Choose no punctuation:

between a subject and its verb, and between a verb and its object;
before an essential clause or name (Students who finish early may leave; the poet Ahmed Shawqi);
between a preposition and its object (in the garden, not in, the garden);
before a clause that begins with that used as an object (She said that she was tired);
between two items joined by and (bread and cheese);
before a short essential time or reason clause at the end of a sentence (We left when the film ended).

Boundary toolkit: joining two complete sentences

Correct ways to join Sentence 1 + Sentence 2	Example
Period	The road was closed. We walked.
Semicolon	The road was closed; we walked.
Comma + FANBOYS	The road was closed, so we walked.
Colon (when sentence 2 explains sentence 1)	We had no choice: the road was closed.
✗ Comma alone (comma splice)	The road was closed, we walked.
✗ Nothing (run-on)	The road was closed we walked.

Worked examples

Each example is part of an ACT-style essay. The underlined portion is shown in bold.

Worked example 1. "The museum's newest exhibit, a collection of Pharaonic jewellery opened last week."