SAT Grammar: Commas, Semicolons, and Colons
The punctuation rules tested on every Digital SAT, with the exact patterns College Board uses.
The Core Rules
These three marks drive most SAT punctuation questions.
- Comma + FANBOYS to join two independent clauses.
- Semicolon to join two independent clauses without a conjunction.
- Colon to introduce a list, definition, or elaboration after an independent clause.
- Em dash pairs to insert extra information mid-sentence.
- Single comma to set off introductory or non-essential elements.
The Independent Clause Test
Before picking any punctuation, check both sides of the mark. If both sides are complete sentences, you need a semicolon, period, or comma + FANBOYS. If only one side is complete, most punctuation marks won't fit.
What to do after reading this
- Turn the article into one action: a bank drill, a timed module, or a score calculation.
- Write down the exact skill or habit you are testing.
- Review the result before reading another guide.
Related SAT guides
- SAT Punctuation Rules: A Complete Summary
Every punctuation rule tested on the Digital SAT, compressed into a single cheat sheet you can memorize in an afternoon.
- SAT Subject-Verb Agreement: Every Pattern Tested
A guide to subject-verb agreement on the Digital SAT, including the distractors College Board uses most often.
Mistakes to avoid
- Reading multiple guides without doing practice between them.
- Using broad practice when the article points to a narrow skill.
- Treating format knowledge as score improvement before testing it under time.
Use this in practice
Practice on 1600.now
Apply what you just read. Run the numbers in the SAT score calculator, take a full Digital SAT module, or drill targeted skills in the question bank.
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