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Run-On Sentences

Run-On Sentences

Author: Martina Shabram

In this lesson, students will learn how to identify and correct run-on sentences.

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Source: [image of overflowing cup, public domain, http://mrg.bz/QXakRX] [image of knife, public domain, http://bit.ly/1PsSWpu] [image of dog on bed, public domain, http://mrg.bz/b3rWIb]

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Hello, students. My name is Dr. Martina Shabram. And I will be your instructor for today's lesson. I'm genuinely excited to teach you these concepts. So, let's get started. So what's the plan for today? Well, we're going to cover run-on sentences. We'll learn how to identify a run-on when we see it, and then practice some solutions for fixing these sentences.

Let's begin by reviewing what makes up a proper correct sentence. Recall that a sentence has at least three ingredients-- subject plus verb plus full thought. A clause made up of just those three elements is called an independent clause. That will look something like this.

See the subject and the verb? And note that this is all on its own an entire thought. So this is a full sentence. Now a sentence can have more than one independent clause and still be grammatically correct.

Take for example, this sentence. You can see that there are two independent clauses here. Each has its own subject and its own verb and makes up a complete thought. So these two independent clauses could be two separate sentences.

But to show how these two thoughts are connected, we've used a coordinating conjunction to unite them into one sentence. Note that we have the first clause, then a comma and the coordinating conjunction and then the second clause. That comma is essential with a compound sentence like this.

So we've got a handle on what makes a full sentence. So then we have to figure out what a run-on sentence is. A run-on sentence is a sentence that's too full. It's overflowing.

Technically, a run-on sentence is a sentence that includes multiple independent clauses that are not connected correctly. This will happen when there are multiple clauses that are connected without the use of correct punctuation or either coordinating or subordinating conjunctions.

Those three tools-- punctuation, coordinating conjunctions, and subordinating conjunctions-- will be how we fix run-ons. But we'll get to that in a minute. For now, let's learn how to spot the problem.

And run-ons really are a problem because they can be really confusing for our readers and make our sentences unclear. So we need to become expert run-on hunters. The first thing we'll look for is a comma splice. This is one of the most common causes of a run-on.

A comma splice is a grammatically incorrect sentence in which a comma separates two or more independent clauses. So remember how in our previous example we had an independent clause plus a comma and a coordinating conjunction plus another independent clause? Well, what if we took out that coordinated conjunction.

Now we have two independent clauses, but instead of being united, think of that comma as a knife splicing them into two pieces. This is not grammatically correct in English. Because instead of bringing these two ideas together, that comma splice awkwardly separates them.

Let's look at another sentence. Now is this a run-on or not? Well, to find out, ask yourself these questions about this sentence. First, how many pairs of subjects and verbs are there. Well, I see "friends" plus "are coming," and "we" plus "are having." Well, that's two.

So now we have to ask, how many independent or dependent clauses are there? OK. That first clause is an independent clause with a subject, a verb, and a full thought. Then I see in the second clause, "and we are having cake." Oh, well, that's a dependent clause. So now we need to check. What job are the coordinating and/or subordinating conjunctions performing?

Well, I see a coordinating conjunction-- and. So is this sentence a run-on? Well, we have to know if the coordinating conjunction is doing its job. And here, I see that, no, it's not. How do I know? Well, I don't see it paired with a comma. Therefore, we know that this is a run-on sentence.

We've spotted a run-on in the wild. How do we fix it? There are actually a few different ways to correct run-on sentences. Which method you choose will depend on what kind of run-on you're dealing with, how you want each sentence in the paragraph to work together, and what your overall goal is for the sentence, paragraph, or paper.

In short, correcting a run-on is about choosing the way you want your sentences to sound. So let's practice these methods and then you can make an informed choice about how to change any sentence.

The first fix is to break apart the sentence into its independent clauses, each of which will transform into its own sentence, punctuated and capitalized correctly. The second solution is to connect the two classes using a coordinating conjunction and a comma. The third correction is a semi-colon, which is a piece of punctuation specifically designed to connect two independent clauses into a sentence that isn't a run-on. And finally, we can remedy this error by adding in a subordinating conjunction. Problem solved.

So let's see how this might work in a paragraph. Wow, there are a lot of errors here. Let's fix that. In the first sentence, we have two independent clauses without proper connection. So let's add in a coordinating conjunction to make these two sentences connect more clearly.

In the second sentence, we have two independent clauses united by a coordinating conjunction. But, what are we missing? The comma.

Now in the third sentence, we have two compound sentences incorrectly connected, which is, well, it's pretty confusing. So let's add in a semi-colon to clear that sentence up.

All right, last sentence-- a propositional phrase and then two independent clauses. Let's use a subordinating conjunction to make that second clause dependent. Now we have a really good paragraph.

So now you know how to fix these run-ons. But we can also work on avoiding them altogether as we're writing. Now how do we do that? Well, we know that in a typical sentence in English, it's not necessary to include more than two clauses. Having multiple clauses doesn't necessarily lead to a run-on, but it can.

And in fact, it's a lot easier to end up making the kind of grammatical error that leads to a run-on when you're writing a sentence with lots of clauses. So you can avoid run-ons by keeping your sentences to two clauses or less.

Another way to avoid the run-on trap is to always think about how you started a sentence as you're writing it. If you're so far into a sentence that you can't remember the way it began, well, you might just be churning out a run-on. So if you find you're writing a sentence that seems like it's becoming a run-on, go ahead and cut it apart into two sentences.

Find the first independent clause and let it be its own sentence. Then move on to the next few clauses to see how those can be punctuated or written correctly as a sentence. Now you have two complete and correct sentences instead of one ungainly run-on.

So what did we learn today? Well, we reviewed the structure of a correct sentence and how independent and dependent clauses can be united into complete sentences. Then we looked at the many ways that clauses can come together incorrectly to form run-on sentences. We practiced some methods for fixing those run-ons. And finally, we learned some tricks for preventing sentences from running on as we're writing them.

Well students, I hope you had as much fun as I did. Thank you.

Notes on "Run-On Sentences"


(00:00 – 00:09) Introduction

(00:10 – 00:20) What are we going to learn today

(00:21 – 01:27) Sentence and Clause Review

(01:28 – 03:59) What is a run-on sentence?

(04:00 – 05:00) How to Fix a Run-On

(05:01 – 05:50) Fixing Run-Ons in a Paragraph

(05:51 – 06:53) Preventing Run-Ons

(06:54 – 07:19) Recap and Goodbye

Terms to Know
  • Comma Splice

    A grammatically incorrect sentence in which a comma separates two or more independent clauses.

  • Run-On Sentence

    A sentence that includes multiple independent clauses that are not connected correctly.