SAT Grammar / Sentence Structure

Comma Splices, Run-Ons, and Fragments

Choose punctuation on SAT grammar questions by checking whether each side could stand alone as a sentence. Catch comma splices, run-ons, and fragments, including ones hidden in longer sentences.

Part of the full libraryOpens January 2, 2027 · $97 for a year
What’s included

Two complete sentences can run together with nothing between them.

A sentence about a storm runs two sentences together with nothing between them. The demo finds where the first sentence ends, shows that the words on each side could stand alone, marks a comma there as a comma splice, and puts a semicolon in its place. Then it asks which mark can join two short sentences.

You’ll leave with these skills

  1. Join two complete sentences with a period or a semicolon
  2. Join two sentences with a comma and “and,” “but,” or “so”
  3. Punctuate an introductory dependent clause

This lesson is part of the full library

207 lessons that teach every skill the SAT tests
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  • 24Grammar
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