Los Angeles Valley College



image: two running sneakers and run-ons


Run-on sentences are one of the most common writing errors. Many students have trouble locating and fixing run-on sentences. This handout will show you how to identify and fix run-on sentences in your essays.


Run-on sentences have two complete sentences that lack correct punctuation. Run-on sentences can be confusing to the reader because they do not show where one idea ends and the next idea begins. There are two types of run-on sentences: the fused sentence and the comma splice.


A fused sentence is a sentence that has two or more complete sentences without the correct punctuation between them. A comma splice is two or more complete sentences held together by only a comma.

Example of a fused sentence:

Bob went to the store he bought some apples.

Example of a comma splice:

Bob went to the store, he bought some apples.

"Bob went to the store" and "He bought some apples" are complete sentences. A complete sentence is called an independent clause. An independent clause contains a subject and a predicate, which is the portion of the sentence that contains the verb. Both of these sentences can be fixed by using a period, semicolon, colon, coordinating conjunction, subordinating conjunction, or a conjunctive adverb or transitional phrase.

  • Adding a period makes two complete sentences:

    Bob went to the store. He bought some apples.

A period is used when a sentence is complete. Any independent clause can be ended with a period.


[Separating sentences with a period is the easiest way to correct fused sentences and comma splices. However, it can lead to incoherent paragraphs. Combining sentences and using transitional phrases will help remedy an incoherent sentence. Please see the Transitional Phrases handout for additional information.]

  • Adding a semicolon or a colon makes one complete sentence:

    Bob went to the store; he bought some apples.

A semicolon should only be used when the ideas are closely related. The sentences should logically "flow" together. In cases where it is unclear whether or not the ideas are closely related, it is probably safer to not use the semicolon.

  • Adding a comma and coordinating conjunction will make one complete sentence:

    Bob went to the store, and he bought some apples.

A coordinating conjunction gives equal weight to both sentences. In other words, each independent clause is equally important. The most common coordinating conjunctions for, and, nor, but, or, yet, and so can be easily recalled from the acronym FANBOYS.

image: horn


Coordinating Conjunctions

For And Nor But Or Yet So = FANBOYS

Use the FANBOYS formula to combine independent clauses:


Subject + Predicate, {FANBOYS} Subject + Predicate


  • Adding a subordinating conjunction:

    After Bob went to the store
    , he bought some apples.
    Bob bought some apples after he went to the store.

Adding a subordinating conjunction to one of the two independent clauses creates an independent clause and a dependent clause. As stated earlier, an independent clause is a complete sentence that contains a subject and a predicate. A dependant clause contains a subject, a verb, and a subordinating conjunction.

Unlike a coordinating conjunction, a subordinating conjunction creates a sentence in which the ideas are given an unequal weight because one sentence is dependent on another. The dependent clause requires an independent clause. Without the independent clause, the dependant clause is a fragment.


Common Subordinating Conjunctions




Use these formulas to use subordinating conjuctions:


{Subordinating Conjunction} Subject + Predicate, Subject + Predicate


Subject + Predicate {Subordinating Conjuction} Subject + Predicate


  • Adding a semicolon, a conjunctive adverb or transitional phrase, and a comma makes a complete sentence:

    I have to study; therefore, I cannot go swimming this afternoon.

A conjunctive adverb or transitional phrase acts as a bridge that connects two sentences. However, if the bridge lacks a semicolon and a comma, it will collapse. A semicolon and comma are always necessary whenever a conjunctive adverb is used.


Common Conjunctive Adverbs and Traditional Phrases

For Example



Use these formulas to use conjunctive adverbs:


Subject + Predicate; {Conjunctive Adverb}, Subject + Predicate



image; pair of glasses Exercise:


Try to find the fused sentences and comma splices in the following essay and try to correct them using the guidelines in this handout.

Did you ever hear of the Wobblies, not many people have these days. That's a shame they did at least two things for which they should be remembered. They probably saved the labor movement in America, they definitely gave American folk music some of its most unforgettable songs. No one really knows how they got their nickname almost everyone knows a song or two that they inspired.


The Wobblies were the members of the Industrial Workers of the World, this union was a small but militant coalition of radical labor groups. The Wobblies could not get along with the major union groups of the day, in fact, they alienated most of those groups.


The major unions disliked the Wobblies immensely, nevertheless they learned some valuable lessons from them. The first lesson was to avoid getting involved in politics. If there was one thing the Wobblies hated more than capitalism, it was politics. The Wobblies avoided politics for one good reason, they believed that political affiliation caused the death of unions. What else did the major unions learn, they learned to deal realistically with workers' problems. Major unions learned new recruiting techniques from the Wobblies. In addition, they copied the Wobblies in devoting their energy to nuts-and-bolts issues affecting the workers.


The major unions never recognized their debt to the Wobblies, the debt was still there for later historians to see. Historians began to compile the story of American labor unions, then they finally recognized the contributions of the Wobblies.

(Hacker 151)


This handout is based on the following text:

Hacker, Diana and Wanda Van Goor.  Bedford Basics: A workbook

for Writers. 2nd ed.   Boston: Saint Martin's, 1994. 147-151.


The above text is available at the Writing Center.



Rev. Oct '02



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