Run-On Sentences and Comma Splices Worksheet Generator
Make printable run-on sentences and comma splice worksheets in seconds. Students identify whether a sentence is complete, a run-on, or a comma splice, choose the best correction, rewrite the sentence, split it into two sentences, add a comma and a conjunction, or fix the punctuation — repairing errors with periods, semicolons, coordinating conjunctions, and subordinating conjunctions. Pick a focus, sentence set, and difficulty, or paste your own sentences, then print or download a clean PDF with an answer key. Free, no sign-up, and everything stays in your browser.
PDF puts the answer key on its own page.
Run-On Sentences and Comma Splices Worksheet
Mixed review · Mixed sentence editing
Name: ______________________ Date: ____________
Read each sentence, then identify or fix the error.
- 1.
Is this sentence complete, a run-on, or a comma splice?
The museum was crowded we waited in line.
- A)Comma splice
- B)Complete sentence
- C)Run-on sentence
- 2.
Is this sentence complete, a run-on, or a comma splice?
The market opened early, the vendors set up their stands.
- A)Comma splice
- B)Complete sentence
- C)Run-on sentence
- 3.
Is this sentence complete, a run-on, or a comma splice?
The bell rang, the students lined up.
- A)Comma splice
- B)Complete sentence
- C)Run-on sentence
- 4.
Is this sentence complete, a run-on, or a comma splice?
The students opened their notebooks the lesson began.
- A)Run-on sentence
- B)Complete sentence
- C)Comma splice
- 5.
Is this sentence complete, a run-on, or a comma splice?
We watered the garden after lunch.
- A)Run-on sentence
- B)Comma splice
- C)Complete sentence
- 6.
Is this sentence complete, a run-on, or a comma splice?
The birds sang in the trees the squirrels ran across the yard.
- A)Run-on sentence
- B)Complete sentence
- C)Comma splice
- 7.
Is this sentence complete, a run-on, or a comma splice?
The bakery smelled wonderful this morning.
- A)Complete sentence
- B)Comma splice
- C)Run-on sentence
- 8.
Is this sentence complete, a run-on, or a comma splice?
Our teacher read a story to the class.
- A)Comma splice
- B)Run-on sentence
- C)Complete sentence
- 9.
Is this sentence complete, a run-on, or a comma splice?
The soup was hot, we waited to eat.
- A)Complete sentence
- B)Run-on sentence
- C)Comma splice
- 10.
Is this sentence complete, a run-on, or a comma splice?
The turtle moved slowly, it still finished first.
- A)Run-on sentence
- B)Complete sentence
- C)Comma splice
Answer key
- 1.C) Run-on sentence — This is a run-on sentence because two complete sentences run together with no punctuation between them.
- 2.A) Comma splice — This is a comma splice because a comma alone cannot join two complete sentences.
- 3.A) Comma splice — This is a comma splice because a comma alone cannot join two complete sentences.
- 4.A) Run-on sentence — This is a run-on sentence because two complete ideas need punctuation and a joining word.
- 5.C) Complete sentence — This is a complete sentence with one clear, complete thought.
- 6.A) Run-on sentence — This is a run-on sentence because two complete sentences run together with no punctuation between them.
- 7.A) Complete sentence — This is a complete sentence with one clear, complete thought.
- 8.C) Complete sentence — This is a complete sentence with one clear, complete thought.
- 9.C) Comma splice — This is a comma splice because a comma alone cannot join two complete sentences.
- 10.C) Comma splice — This is a comma splice because a comma alone cannot join two complete sentences.
Answer Key · Run-On Sentences and Comma Splices Worksheet
Mixed review · Mixed sentence editing
- 1.C) Run-on sentence — This is a run-on sentence because two complete sentences run together with no punctuation between them.
- 2.A) Comma splice — This is a comma splice because a comma alone cannot join two complete sentences.
- 3.A) Comma splice — This is a comma splice because a comma alone cannot join two complete sentences.
- 4.A) Run-on sentence — This is a run-on sentence because two complete ideas need punctuation and a joining word.
- 5.C) Complete sentence — This is a complete sentence with one clear, complete thought.
- 6.A) Run-on sentence — This is a run-on sentence because two complete sentences run together with no punctuation between them.
- 7.A) Complete sentence — This is a complete sentence with one clear, complete thought.
- 8.C) Complete sentence — This is a complete sentence with one clear, complete thought.
- 9.C) Comma splice — This is a comma splice because a comma alone cannot join two complete sentences.
- 10.C) Comma splice — This is a comma splice because a comma alone cannot join two complete sentences.
How to use the run-on sentences & comma splices worksheet generator
- 1Choose a practice focus, sentence set, and difficulty, or paste your own sentences.
- 2Pick a question format: identify the error, choose the best correction, rewrite, split, add a conjunction, fix punctuation, or mixed.
- 3Set how many questions, then toggle the name line, instructions, and answer key.
- 4Press Regenerate for a fresh set, then print or download a PDF with the answer key.
When this is useful
Identify run-ons and comma splices
Clear sentences give students focused practice labeling each one as complete, a run-on, or a comma splice.
Fix run-on sentences
The rewrite, split, and fix formats ask students to repair two fused complete sentences correctly.
Fix comma splices
Students learn that a comma alone cannot join two sentences, then choose a stronger way to connect them.
Practice correction strategies
Use periods, semicolons, comma plus a coordinating conjunction, and subordinating conjunctions as repair tools.
ELL and language support
Identify and choose formats help multilingual learners see where one sentence ends and the next begins.
Your own sentences
Paste your own sentences so the editing practice matches your class writing or a recent lesson.
Examples to try
An identify-the-error worksheet
Use the identify format so students label each sentence as complete, a run-on, or a comma splice.
A choose-the-best-correction worksheet
Use the choose format so students pick the one correct repair from four close choices.
A split-into-two-sentences worksheet
Use the split format so students rewrite a run-on as two complete sentences with a period.
An add-a-conjunction worksheet
Use the add-a-conjunction format so students join two clauses with a comma and and, but, or so.
A fix-the-punctuation worksheet
Use the fix-punctuation format so students add a period, semicolon, or comma and conjunction.
A worksheet from your own sentences
Paste sentences, or simple sentence = run-on lines, to match your class.
Tips for better results
Start by reading aloud
When a sentence runs out of breath, two complete thoughts are probably joined without the right punctuation.
Test each half
If both sides of a comma could stand alone as sentences, a comma alone is a splice and needs a stronger fix.
Begin with the period fix
The split format and beginner difficulty keep early practice on separating run-ons into two clear sentences.
Add semicolons later
The challenge difficulty introduces semicolons and subordinating conjunctions once students are confident.
Print the answer key separately
The PDF puts the answer key on its own page, so you can keep it apart from the student copy.
Pair it with grammar tools
Follow with a compound and complex sentences worksheet or a conjunctions worksheet for more sentence practice.
How the run-on sentences & comma splices worksheet generator works
Built-in worksheets use original, classroom-safe sentences written for this tool. Each item pairs two clean independent clauses with one error type — complete, run-on, or comma splice — and one best repair strategy, then derives the error sentence and every correction from those clauses, so the answer key is always defensible. A run-on fuses two complete sentences with no punctuation, a comma splice joins them with only a comma, and a complete sentence is left as is — and each example fits one label clearly, so there is never more than one right answer.
Identify questions have one deterministic answer, and choose-the-best-correction questions place the correct repair beside three clearly-wrong ones — the comma splice, the run-on, and a semicolon misused with a conjunction — so there is exactly one correct answer with no duplicate choices. The rewrite, split, add-a-conjunction, and fix-punctuation formats give students room to write, with the answer key showing a period, semicolon, comma-plus-conjunction, or subordinating fix. Custom items let you bring your own; the type and strategy are normalized or safely inferred from clear structure only, and when a custom item lacks enough clause data it uses a teacher-check sample instead of inventing one.
Everything is generated on your device. Press Regenerate for a fresh set from the same options, and print or save a clean PDF, instantly and for free. Your custom sentences and settings never leave your browser.
Private by design
- No account and no sign-up. Just open it and start.
- Everything runs on your device, so the worksheet settings you choose and any sentences you paste stays with you.
- Nothing you create is uploaded. No values, names, scores, or generated content are sent to our servers.
- We use Google Analytics only for basic, anonymous pageview counts. It never receives what you enter into the tool.
Frequently asked questions
Is this run-on sentences worksheet generator free?
Yes, completely free, with no account and no limit on how many worksheets you make. There's no watermark on the printed worksheet.
Can I print the worksheet?
Yes. Use the Print button to send the worksheet straight to your printer. Only the worksheet prints, with the sentences and questions, and nothing else from the web page.
Can I download a PDF?
Yes. Download a clean PDF built right on your device, with the worksheet on the first pages and, when enabled, an answer key on its own page.
Can students practice comma splices and fix run-on sentences?
Yes. The identify format asks students to spot run-ons and comma splices, and the rewrite, split, add-a-conjunction, and fix-punctuation formats have them correct the errors.
Can students choose different correction strategies?
Yes. Corrections use periods, semicolons, a comma plus a coordinating conjunction, and subordinating conjunctions, and the difficulty setting controls which strategies appear.
Can students choose the best correction from multiple choices?
Yes. The choose format shows an error sentence with four close options and exactly one correct repair, so students pick the best fix.
Can I use custom sentences?
Yes. Switch to custom and paste your own items, using labels or simple sentence = run-on lines. Your sentences stay in your browser and are never saved or uploaded.
Does this use AI, and are my custom sentences saved?
No. This is a browser-only worksheet builder. It does not use AI to write sentences or decide answers, and nothing you type is stored or sent anywhere.
Helpful supplies for this activity
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Dry erase pockets
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