Handout Topic: Run-on Sentences

What are run-on sentences?

A run-on sentence results from two or more complete sentences being connected without any punctuation.

How to find a run-on sentence:

The best way to find a run-on sentence is to determine whether there is more than one independent clause in the same sentence without punctuation. If there are two subjects (who or what the sentence is about) or a subject and its pronoun (he, she, it, they etc.) in the same sentence and they are not separated with proper punctuation, then a run-on sentence results.

  • I ran across the road it was very dangerous. (two independent clause)
  • I ran across the road. It was very dangerous. (fixed with proper punctuation)

Be careful not to turn a run-on sentence into a comma splice. A comma splice is an error that results from using a single comma to separate two independent clauses. Run-on sentences cannot be fixed with a single comma. For more information, see the WRC handout on comma splices.

There are four main ways to fix a run-on sentence:

1. Separate the two clauses with a period.

e.g. Jim is the fastest runner in the class he wins all of the races.
Fixed Jim is the fastest runner in the class. He wins all of the races.

2. Separate the clauses with a semi-colon.

e.g. I have owned four different guitars my first guitar was a Gibson Explorer.
Fixed I have owned four different guitars; my first guitar was a Gibson Explorer.

3. Use a comma with a coordinating conjunction

(e.g. and, but, or, for, yet, nor, so) to separate the clauses.

e.g. Our parents did not like the loud music we could not stop dancing.
Fixed Our parents did not like the loud music, but we could not stop dancing.

4. Use a subordinating conjunction

(e.g. although, after, before, unless, as, because, even though, if, since, until, when, while) and a comma to separate the two clauses.

e.g. Stephanie worked all week she still partied on Fridays.
Fixed Although Stephanie worked all week, she still partied on Fridays.