Online Writing Lab

Roane State Community College

Run-on Sentences

A run-on sentence is more than one sentence joined together incorrectly. It’s called a "run-on" because it "runs on" with more than one idea.  Consider this example of a run-on sentence:

I have a poor backhand I don’t play tennis well.

Do you see that two main ideas are actually stated here? 1) I have a poor backhand.  2) I don’t play tennis well.  These two main ideas can’t be joined together without using appropriate punctuation. Without proper punctuation and/or a joining word, we have a run-on sentence.  Here are some examples of ways that these sentences can be joined correctly:

I have a poor backhand. I don’t play tennis well. (period added)

I have a poor backhand; I don’t play tennis well. (semicolon added)

Because I have a poor backhand, I don’t play tennis well. (subordinating conjunction or dependent word added to the beginning of the sentence; comma is needed between these ideas)

I don’t play tennis well because I have a poor backhand. (subordinating conjunction or dependent word as the connecting word; no comma is needed between these ideas)

I have a poor backhand, so I don’t play tennis well. (conjunction and a comma added)

I have a poor backhand; therefore, I don’t play tennis well. (semicolon and conjunction)

To find run on sentences, read each of your sentences closely to figure out where one sentence ends and the new one begins. Then separate the ideas with the appropriate punctuation and/or transition word.