By Glyn Caddell, BSME · Author of Digital SAT Math Secrets · Tutoring since 2008 — Updated August 10, 2026
Punctuation questions on the Digital SAT ask students to choose the answer choice with the correct punctuation that fits into the blank in a text. Punctuation questions include commas, colons, semicolons, dashes, parentheses, and apostrophes. Punctuation questions appear on approximately 13.6% of the Digital SAT Reading & Writing section. These questions fall under Standard English Conventions according to the College Board categories.
Punctuation Lesson
The lesson covers the types of punctuation questions that show up on the Digital SAT. The lesson will cover what these questions look like, what punctuation is used to join sentences, how transitions are punctuated, how an appositive is punctuated, what apostrophes are for, and how to punctuate if-then statements.
What Do Punctuation Questions Look Like?
Punctuation questions can be identified by looking at the answer choices. Almost everything about the answer choices will remain the same except for the punctuation.
What Punctuation is Used to Join Sentences?
To join sentences, a semicolon, comma and conjunction, or a colon can be used.
How to Join Sentences with a Semicolon
To join two sentences with a semicolon, change the first letter of the second sentence to a lowercase letter (unless it is a proper noun) and replace the period at the end of the first sentence with a semicolon.
Important: do not use a conjunction after the semicolon. Simply switch the period at the end of the first sentence into a semicolon.
Example:
I like pizza. It is delicious.
becomes
I like pizza; it is delicious.
How to Join Sentences with a Comma and a Conjunction
To join two sentences with a comma and a conjunction, change the first letter of the second sentence to a lowercase letter (unless it is a proper noun), replace the period with a comma, and add a conjunction that logically joins the sentences together.
The only acceptable conjunctions can be remembered by the acronym FANBOYS: for, and, nor, but, or, yet, & so.
Example:
I don’t like pepperoni pizza. It was the only option available.
becomes
I don’t like pepperoni pizza, but it was the only option available.
When to Use a Colon on the Digital SAT
A colon can be used to introduce a quotation/list of items or to separate two clauses of which the second expands or illustrates the first.
On the SAT, whatever is before the colon must be a full sentence. Whatever is after the colon can be anything: a word, a phrase, a sentence, etc.
Example:
Arnold believes that there is another explanation for global warming: worldwide habitat destruction.
In the example, “Arnold believes that there is another explanation for global warming” is an independent clause. The part “worldwide habitat destruction” expands on what was just said. It is his other explanation for global warming, so it can follow the independent clause after a colon.
How are Transitions Punctuated?
Transitional phrases cannot be used as conjunctions. The two sentences must either remain two separate sentences or be joined with a semicolon.
[SENTENCE]; [TRANSITIONAL PHRASE], [SENTENCE].
Example:
I don’t like pepperoni pizza; however, it was the only option.
How is an Descriptive Language Punctuated?
Descriptive language can be separated with commas, parenthesis, or dashes, but it must be consistent. If a comma is used in the beginning, a comma must be used at the end. If a dash is used in the beginning, a dash has to be used at the end. If an open parenthesis is used at the beginning, a closed parenthesis has to be used at the end.
Example:
Robert, who was raised in a family of athletes, excels at almost every sport he plays.
In the above sentence, the independent clause is simply:
Robert excels at almost every sport he plays.
The appositive (descriptive language) is:
who was raised in a family of athletes
and is correctly separated with commas before and after it.
What are Apostrophes Used For?
Apostrophes are used for contractions or for possession.
Apostrophes for Contractions
Apostrophes can be used in contractions to show that letters are missing (“they are” becomes “they’re”) or to show possession.
Apostrophes for Possession
Apostrophes can be used to show possession.
For singular nouns, add an apostrophe and s (‘s) to show possession.
Singular nouns:
[noun]‘s shows possession.
Example: The girl’s phone broke.
Plural nouns:
If a plural noun ends in an s, just add an apostrophe to the end of the plural noun.
[nouns]’ shows possession for words that end in s because they are plural.
Example: The players’ coach was overcome with joy and relief when the kicker made the game-winning field goal.
If the plural noun doesn’t end in an s, then add an apostrophe and s like normal:
Example: The children’s school is closed.
Children is plural and doesn’t end in s, so add an apostrophe and an s at the end to make it possessive.
What is Correct: Its or It's?
Its and It’s are slightly complicated when it comes to the rules.
The rule for contraction is followed. The rule for possession isn’t.
It’s is the contraction form of “it is” and “it has”. The apostrophe is used to show that letters are missing.
The complicated part is when it comes to possession. Normally apostrophe s is for possession. However, for the word it, only add an s for possession.
How to Punctuate If-Then Statements
To punctuate if-then statements, a comma is used after the if part of the sentence.
If __________________________, then__________________________.
If it keeps raining, then the sewers will get backed up.
The word “then” isn’t necessary.
If __________________________, __________________________.
If it keeps raining, the sewers will get backed up.
If the order is reversed, a comma is not used.
The sewers will get backed up if it keeps raining.
Tips
- Always try to identify subjects and verbs in the sentences. That will help you identify if you have one or more independent clauses.
- Remember to put a comma before a conjunction when joining two independent clauses.
Example
The architect designed the building to maximize natural light, reduce energy use, and create flexible public spaces ____ the project still faced criticism from residents concerned about increased traffic.
Which choice completes the text so that it conforms to the conventions of Standard English?
A) , a goal that appealed to city officials,
B) — a goal that appealed to city officials —
C) ; a goal that appealed to city officials
D) . A goal that appealed to city officials,
Video Explanation
Text Explanation
Answer: D
The phrase “a goal that appealed to city officials” may look like an appositive describing the previous clause, but the text that follows—“the project still faced criticism…”—is a new independent clause. A comma or dash pair would incorrectly create a run-on. A period correctly ends the first sentence, and the following phrase introduces the next sentence.
Practice Problems with Video Explanations
Here is a set of practice Digital SAT punctuation practice problems. After selecting an answer, press “See Answer” to see the correct answer and a video explanation showing how to properly solve the questions. At the end of the set, after you press “Submit”, you’ll be able to see all of the questions, answers, and video explanations to review.
For more practice like this, enroll in our on-demand SAT prep course here: https://caddellprep.com/sat/prep/on-demand/
Common Mistakes
Here are two common mistakes students make when answering punctuation questions.
Comma Before "And" When Joining Sentences
If two sentences are joined using a conjunction (normally “and”), there must be a comma before the conjunction.
Assuming an Appositive Belongs at the End of One Sentence Instead of the Beginning of the Next Sentence
A common mistake on difficult punctuation questions is assuming the text in the blank is descriptive language for the sentence before the blank, but it is actually a modifier for the following sentence.
Related Topics
Transitions and Modifiers are topics related to Punctuation.
Transitions
Punctuation questions are related to transition questions because both require students to understand how ideas are connected. In some punctuation questions, students need to determine whether two ideas should be connected with a comma and conjunction, a semicolon, a period, or a colon. Transition questions test a similar skill by asking students to choose the word or phrase that best shows the relationship between ideas. Therefore, practicing transition questions can help students better understand the logic behind punctuation questions.
Modifiers
Punctuation questions are related to modifier questions because descriptive information is often set off by punctuation. For example, commas, dashes, or parentheses may be used to separate extra information from the rest of the sentence. In modifier questions, students need to determine what that descriptive information logically describes. Therefore, practicing modifier questions can help students better understand how punctuation affects sentence meaning.
All Reading & Writing Topics
All of our reading & writing topics are available here: https://caddellprep.com/sat/reading-writing/ for you to review and improve on your SAT. There are lessons, practice problems, and video explanations for you. If you need more help, try our on-demand SAT course with video lessons, practice tests, and sets of questions for each topic: https://caddellprep.com/sat/prep/on-demand/
Glyn Caddell
Glyn Caddell holds a BS in Mechanical Engineering from NJIT and has been tutoring New York City students since 2008. He founded Caddell Prep in 2012 and is the author of Digital SAT Math Secrets: Lessons & Tricks to Quickly Improve to a Perfect 800 on the Math Test, which contains over 900 practice problems and is used in Caddell Prep’s SAT math classes. He is founding president of the Staten Island Technical High School alumni association and teaches every lesson on this site personally.
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