Run-On Sentences: What They Are, Examples & How to Fix Them
A run-on sentence is not simply a long sentence. It is two or more independent clauses joined without proper punctuation or a conjunction. Run-ons confuse readers because they blur the boundary between ideas. The good news: they are easy to fix once you know how to spot them.
What Is a Run-On Sentence?
A run-on sentence occurs when two or more independent clauses — complete thoughts that could stand alone as sentences — are connected without appropriate punctuation or conjunctions. There are two types of run-on sentences, and understanding the distinction helps you identify and fix them.
Fused Sentence
Two clauses with no punctuation at all
"I love writing it helps me think."
Comma Splice
Two clauses joined only by a comma
"I love writing, it helps me think."
Run-On vs Long Sentence
A common misconception: long sentences are not automatically run-ons. A sentence can be 100 words long and be grammatically correct if it uses proper punctuation and conjunctions. Conversely, a run-on can be as short as six words: "I run he walks." Length is not the issue — the connection between clauses is.
Long but correct
"She walked through the old market, past the fish stalls and the flower vendors, under the arches where pigeons nested, and into the square where the fountain had been dry for years."
Short but run-on
"She walked home he stayed behind."
Four Ways to Fix a Run-On Sentence
1. Use a period
The simplest fix. Split the run-on into two separate sentences. This works best when the ideas are distinct and don't need a visible connection. "I love writing. It helps me think clearly."
2. Use a semicolon
A semicolon signals that two ideas are closely related and belong together, but are each complete thoughts. "I love writing; it helps me think clearly." Use this when the relationship between the clauses is obvious and doesn't need a conjunction to explain it.
3. Add a coordinating conjunction
Use a comma followed by one of the seven coordinating conjunctions: for, and, nor, but, or, yet, so (FANBOYS). "I love writing, and it helps me think clearly." This makes the relationship between the clauses explicit.
4. Use subordination
Turn one independent clause into a dependent clause by adding a subordinating conjunction (because, although, when, since, after, before, if, unless). "I love writing because it helps me think clearly." This is the most sophisticated fix — it clarifies which idea is primary and which is supporting.
Run-On Sentence Examples with Fixes
Each example below shows the run-on type, the incorrect sentence, and multiple ways to fix it. Notice that different fixes create different effects — the "right" fix depends on the rhythm and meaning you want.
Fused Sentence
I love writing it helps me think clearly.
I love writing. It helps me think clearly.
I love writing; it helps me think clearly.
I love writing because it helps me think clearly.
Comma Splice
The sun was setting, the sky turned orange and pink.
The sun was setting. The sky turned orange and pink.
The sun was setting; the sky turned orange and pink.
The sun was setting, and the sky turned orange and pink.
Fused Sentence
She finished the novel she immediately started writing another one.
She finished the novel. She immediately started writing another one.
She finished the novel; she immediately started writing another one.
After she finished the novel, she immediately started writing another one.
Comma Splice
The coffee was cold, he drank it anyway.
The coffee was cold. He drank it anyway.
The coffee was cold; he drank it anyway.
The coffee was cold, but he drank it anyway.
Fused Sentence
The deadline was tomorrow he hadn't started the project yet.
The deadline was tomorrow. He hadn't started the project yet.
Although the deadline was tomorrow, he hadn't started the project yet.
Comma Splice
She wanted to go to the party, she had too much work to do.
She wanted to go to the party. She had too much work to do.
She wanted to go to the party, but she had too much work to do.
She wanted to go to the party; however, she had too much work to do.
Fused Sentence
The plot was compelling the characters felt flat.
The plot was compelling. The characters felt flat.
The plot was compelling, but the characters felt flat.
Although the plot was compelling, the characters felt flat.
Comma Splice
He revised the chapter three times, the editor still found errors.
He revised the chapter three times; the editor still found errors.
He revised the chapter three times, yet the editor still found errors.
Even though he revised the chapter three times, the editor still found errors.
How to Spot Run-Ons in Your Writing
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