Recognizing and Editing for Run-ons

Sentence structure problem #2: Run-on sentences

Run-on sentences are probably even more prevalent than fragments. Run-ons raise the anxiety level of students who don’t know how to fix them. They agitate teachers who keep seeing them in essays. They bother bosses who expect their employees to use proper sentence structure in workplace writing.

The term “run-on” is a perfect name for these would-be sentences. A run-on is actually two independent clauses that have been improperly run together. The clauses need to be separated into two sentences or joined into one. Comma splice is the name for a specific kind of run-on in which a comma improperly joins two independent clauses.

Note: People sometimes think that if a sentence is long, it must be a run-on, but that is not necessarily true. Take, for example, the following sentence from Phillip Roth’s 2004 novel A Plot Against America:

Elizabeth, New Jersey, when my mother was being raised there in a flat over her father’s grocery store, was an industrial port a quarter the size of Newark, dominated by the Irish working class and their politicians and the tightly knit parish life that revolved around the town’s many churches, and though I never heard her complain of having been pointedly ill-treated in Elizabeth as a girl, it was not until she married and moved to Newark’s new Jewish neighborhood that she discovered the confidence that led her to become first a PTA “grade mother,” then a PTA vice president in charge of establishing a Kindergarten Mothers’ Club, and finally the PTA president, who, after attending a conference in Trenton on infantile paralysis, proposed an annual March of Dimes dance on January 30—President Roosevelt’s birthday—that was accepted by most schools.

Cover of the paperback Longest Word + Longest Sentence + Longest Novel + Longest Poem, which gives 100-page excerpts from the longest word, sentence, novel, and poem

Source: Longest, IPSI

That one sentence is 142 words long, but it is not a run-on! In fact, extremely long sentences are not unheard of in English and American literature: one sentence runs 4,391 words in James Joyce’s Ulysses; another sentence has 13,955 words in Jonathan Coe’s novel The Rotters’ Club; and a sentence in Nigel Tomm’s The Blah Story reportedly has over two million words!

Conversely, a short sentence can be a run-on. Consider the sentence “Gene studied Roger slept.” It has two independent clauses (“Gene studied” and “Roger slept”) joined without proper punctuation, so it is a run-on.

Two variations of a sentence will illustrate the problem of run-ons:

Choosing a new computer is difficult I may give up and keep my old PC. (two independent clauses run together without proper punctuation)

Choosing a new computer is difficult, I may give up and keep my old PC. (a comma cannot join independent clauses; example of a comma splice)

Let’s look at the most common methods to fix run-ons using the same sentence from above:

Add a comma between the clauses followed by an appropriate coordinating conjunction. Not just any coordinating conjunction will work. It must make sense within the context of the sentence. The conjunction comes after the comma. If the comma is already there, you add only a coordinating conjunction.

Choosing a new computer is difficult, so I may give up and keep my old PC.

Separate them with a semicolon, which serves the same purpose as the comma + the conjunction. This solution works if two independent clauses are closely related. (If you are dealing with a comma splice, change the comma to a semicolon.)

Choosing a new computer is difficult; I may give up and keep my old PC.

Add a period between the two independent clauses, or, in a comma splice, replace the comma that is already there with a period.

Choosing a new computer is difficult. I may give up and keep my old PC.

Make one clause subordinate to the other. To do so, add a subordinating conjunction to the beginning. You may also need to add proper punctuation. In this example, a comma is needed after the subordinate clause that begins the sentence.

Because choosing a new computer is difficult, I may give up and keep my old PC.

If you have trouble with run-ons, you will probably admit that both carelessness—writing too quickly, not paying attention to punctuation, etc.—and a lack of knowledge about sentence structure contribute to errors in that area. Since you now know more about independent clauses, a careful examination of your writing will reveal run-ons and let you fix them.

To check your understanding of run-on sentences, do the brief interactive exercise.