Once you can spot a run-on or a comma splice, you have five ways to fix it. Each one shows the reader a slightly different link between the two ideas.
| Fix | Example | What it shows |
|---|---|---|
| 1. A period | The lights went out. We lit candles. | two separate statements |
| 2. A comma and a coordinating conjunction | The lights went out, so we lit candles. | how they connect (and, but, so …) |
| 3. A semicolon | The lights went out; we lit candles. | closely related; with however: “; however,” |
| 4. A subordinating word | When the lights went out, we lit candles. | time, cause or contrast (when, because, although) |
| 5. A colon (if the second explains the first) | We had one choice: we lit candles. | the second part explains the first |
Key idea
Fix a run-on with a period, a comma plus and, but, or, so, yet, for, nor, a semicolon, a subordinating word, or a colon when the second clause explains the first. Before however or therefore, use a semicolon or a period, not a comma.
Why it works
Choosing the fix is a writing decision. “It snowed. School closed.” is blunt. “Because it snowed, school closed.” shows cause. “It snowed; school closed.” lets the reader make the link. The meaning stays; the emphasis changes.
Worked example: Fix a splice with however
“The test was hard, however I passed.”
- Two independent clauses; however is not a conjunction.
- Semicolon before however, comma after it.
- Or use a conjunction: “The test was hard, but I passed.”
Answer: The test was hard; however, I passed.
Worked example: Choose the link
“We were tired we kept walking.”
- The ideas contrast: tired, yet still walking.
- A contrast word fits: but, yet or although.
Answer: We were tired, but we kept walking. (or: Although we were tired, we kept walking.)
Common mistake
Fixing a splice by putting a comma before however: “It rained, however, we played.” That is still a splice. A conjunctive adverb needs a semicolon or a period before it. And a colon only works when the second clause explains or completes the first.