What Is a Run-on Sentence?: 4 Types of Run-on Sentences

A run-on sentence occurs when a writer joins two or more complete sentences (also called an independent clause) together incorrectly. This creates a long sentence that is difficult to read and confuses the reader. You should avoid creating a run-on sentence when writing unless you are making a stylistic choice.

Here are four ways in which a writer might intentionally or inadvertently craft a run-on sentence:

1. 1. When the writer joins two independent clauses by using a conjunction improperly. There are methods one can use to connect two sentences, and they involve using a conjunction (for example, “and,” “but,” or “or”) or punctuation to create compound sentences. If the writer uses neither, then it’s a fused sentence, made up of two improperly joined sentences. To help you identify this type of run-on sentence, try checking to see whether there are many different subjects (who or what the sentence is about) or more than one complete thought. An independent clause has a subject and a verb at a minimum. See if you have more than one verb or more than one complete thought or phrase.
2. 2. When the writer joins two independent clauses by using a comma improperly. When you join two complete sentences with a comma, without any additional verbiage, it’s called a comma splice. This can also occur when there is a transitional word—”to,” “and,” “like,” “as,” or “too,” for example—between the two clauses. Instead of acting as a transition, it further cements the comma splice. Both occurrences are grammatical errors.
3. 3. When the writer joins two or more incomplete sentences. Some run-on sentences contain sentence fragments, or incomplete sentences, rather than two separate independent clauses. Look for incomplete thoughts or clauses that are missing subjects or verbs in order to spot this kind of run-on sentence.
4. 4. When the writer uses multiple conjunctions to join multiple independent clauses. Called a polysyndeton, it creates a sentence that is difficult to read. Sometimes writers use polysyndetons as a stylistic choice to slow down the pace of the reader, but the structure of a polysyndeton is incorrect from a grammatical standpoint. To help you identify this type of run-on sentence, try to determine whether the sentence is attempting to accomplish too many things at once. Sentences should hold one complete thought and then transition to a second complete thought with either proper punctuation or the use of a single conjunction.

Although run-on sentences are grammatically incorrect, they are still found in popular literature and are sometimes used for dramatic effect. Here are four examples of run-on sentences in well-known books:

1. 1. A Tale of Two Cities by Charles Dickens: “It was the best of times, it was the worst of times, it was the age of wisdom, it was the age of foolishness, it was the epoch of belief, it was the epoch of incredulity, it was the season of Light, it was the season of Darkness, it was the spring of hope, it was the winter of despair, we had everything before us, we had nothing before us, we were all going direct to Heaven, we were all going direct the other way—in short, the period was so far like the present period, that some of its noisiest authorities insisted on its being received, for good or for evil, in the superlative degree of comparison only.”
2. 2. The Handmaid’s Tale by Margaret Atwood: “She’s too young, it’s too late, we come apart, my arms are held, and the edges go dark and nothing is left but a little window, a very little window, like the wrong end of a telescope, like the window on a Christmas card, an old one, night and ice outside, and within a candle, a shining tree, a family, I can hear the bells even, sleigh bells, from the radio, old music, but through this window I can see, small but very clear, I can see her, going away from me, through the trees which are already turning, red and yellow, holding out her arms to me, being carried away.”
3. 3. The Old Man and the Sea by Ernest Hemmingway: “He was an old man who fished alone in a skiff in the Gulf Stream and he had gone eighty-four days now without taking a fish.”
4. 4. Infinite Jest by David Foster Wallace: “Gately’s biggest asset as an Ennet House live-in Staffer—besides the size thing, which is not to be discounted when order has to be maintained in a place where guys come in fresh from detox still in Withdrawal with their eyes rolling like palsied cattle and an earring in their eyelid and a tattoo that says BORN TO BE UNPLEASANT—besides the fact that his upper arms are the size of cuts of beef you rarely see off hooks, his big plus is he has the ability to convey his own experience about at first hating AA to new House residents who hate AA and resent being forced to go and sit up in nose-pore-range and listen to such limply improbably clichéd drivel night after night.”

Create separate sentences, add punctuation, or use the proper conjunctions to keep two clauses together and you can avoid run-on sentences. Try these solutions to fix a run-on sentence:

• Break up your clauses. If you identify a run-on sentence in your work, split it into two separate sentences.
• Consider a semicolon. You can use a semicolon in many different ways, but they work well in many run-on sentences. Use one to break up the first and second clauses, keeping the related thoughts in two distinct groups.
• Put a comma and a coordinating conjunction between the two clauses. Examples of coordinating conjunctions include: “and,” “but,” “for,” “nor,” “or,” “so,” and “yet.”
• Change one clause into a dependent clause and join the two clauses with a subordinating conjunction. Two complete sentences that can stand on their own are independent clauses. A dependent clause can only stand with an independent clause because the dependent clause gives the reader further context or information. Create one sentence by placing a subordinate conjunction, such as “because,” “until,” or “when” between the independent and dependent clause.
• Combine the above rules. You can pair a conjunction with a semicolon or a semicolon with a comma. Or change one sentence to a dependent clause and use a semicolon to bring an additional independent clause into the sentence structure. However you choose to fix a run-on sentence, your goal remains to create clear, simple sentences that are easy for a reader to understand.

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