Fragments and Run-on Sentences

Fragments and Run-on Sentences Video

At its base, a sentence is made up of a subject and a verb. We’ll call this the main clause or the independent clause. But what happens when there’s not a subject or a verb? Or when two clauses aren’t combined correctly?

Hello, everyone, and welcome to this Mometrix video. I hope you’ve got your running shoes on because today, we’ll be learning about sentence fragments and run-on sentences. If we’re going to win this grammar race, we’d better get started!

When you hear the phrase “sentence fragment,” you should immediately begin thinking about pieces, incomplete pieces, or parts of a whole. A sentence fragment is just that; it does not form an independent clause. This means that the sentence is lacking a subject, a verb, or both a subject and a verb. Independent clauses are sentences that stand alone because they contain a subject and a verb in agreement with one another; no other pieces are necessary to consider the sentence complete. Dependent clauses, on the other hand, cannot stand alone because they form incomplete sentences.

Today, we’re going to look at six different types of sentence fragments that you’ll most definitely see in the course of your writing career.

The first type of fragment we’ll look at is the subordinating clause.

Subordinating Clause

The subordinating clause is a sentence that has a dependent clause that needs an independent clause to attach to in order to form a complete sentence. To form this attachment, a subordinating conjunction such as after, although, before, while, whenever, etc. must be used.

Here’s an example:

Before the race


A correction might look as follows:

Before the race, you need to lace up your shoes.


The second type of fragment is the participle phrase.

Participle Phrase

The participle phrase lacks both a subject and a verb. It must also modify a noun (person, place, thing) and be paired with an independent clause.

Here’s an example:

Preparing for the race


In order for this clause to form a complete sentence, we must add an independent clause containing a noun for this clause to modify.

For example:

You ran five miles each day, preparing for the race.


The third type of fragment is an infinitive phrase.

Infinitive Phrase

Infinitive phrases most often involve using the word to within a dependent clause. These phrases can function as nouns, as adjectives describing nouns, or as adverbs describing verbs. While all of this is true, at the end of the day, an infinitive phrase does not have the necessary components to form an independent clause.

Here’s an example:

To run the race


A complete sentence might be:

You are prepared to run the race.


In this example to run the race is functioning as an adverb that describes what the subject is prepared for.

The fourth type of sentence fragment is the verb phrase.

Verb Phrase

A verb phrase, as you might could guess, only contains the verb of a sentence and is missing the subject. These are a little tricky at first glance because the verb phrase seems to be able to stand alone. Since the phrase does not contain a subject, it cannot be an independent clause, thus making it a sentence fragment.

Here’s an example:

Waited at the starting line


In this example, we are not given the who or the what that waited at the starting line. A complete sentence might look like this:

You waited at the starting line to begin the race.


Now we have a subject to go with the verb in our sentence!


Appositives are also a form of sentence fragment. Appositives are used to rename the subject of a sentence but do not take the place of the subject overall.

This one is a little more simply explained with an example:

The ones with the broken laces


By itself, it is clear to see that this clause is meant to define an object. Here’s a correct way to write this sentence:

In a moment of panic, you thought you were wearing the wrong track shoes, the ones with the broken laces.


Now we see that “the ones with the broken laces” could rename the noun shoes. We also see with this sentence that “the ones with the broken laces” could not function as the subject because it would be too unclear as to what was being described.

The final type of fragment we will discuss is the afterthought clause.

Afterthought Clause

You may not have formally heard of this type of sentence fragment, but I guarantee you’ve probably seen it or accidentally used it! Some common afterthought clauses are including, such as, like, for example, especially, etc. Oftentimes, we’ll use these words in our paragraphs to begin and form a sentence. But this is wrong! Let’s look at an example to see how we should and should not use these words:

Including fruits, vegetables, and quality sources of proteins


By itself, this is very clearly not an independent clause, but you’d be surprised how many sentences we see that are written just like this one.

A correct use for the afterthought clause might look like this:

As a runner, you should be sure to eat a healthy and balanced diet, including fruits, vegetables, and quality sources of proteins.


Now that we’ve gone over six main types of sentence fragments, I want to give you a couple of tips for catching fragments in your own writing!

Tips for Catching Fragments

1. Proofreading. Proofreading is a great opportunity for catching sentence fragments and for improving the quality of your work. Proofreading is simply rereading your work once you have completed it and before you submit it anywhere.

2. Reading your sentences aloud, backward. Reading your sentences backward helps your brain to pick up on the awkward wording of fragments that you might not otherwise notice if you read the sentence(s) as is.

Run-on Sentences

Another concept in the race for the most grammatically correct sentence is the run-on sentence.

What’s the problem with a run-on sentence? You’ve got to work extra hard to catch them!

(Anybody? Anybody?)

Anyway, the run-on sentence is a pretty simple concept on paper; however, when reading to yourself or speaking in everyday conversation, it is difficult to notice a run-on sentence.

A run-on sentence occurs when two or more independent clauses are paired together without an appropriate conjunction or punctuation mark. Don’t let the length of a sentence fool you. Length is not a good indicator of whether or not a sentence is running-on; it really comes down to punctuation placement and appropriate separation of the two or more independent clauses featured in the sentence.

Run-on sentences can be fixed by adding end punctuation, by adding a conjunction, or by adding a semicolon. Deciding which solution to use when correcting your run-on sentences will just depend on the makeup of the clauses you’re working with.

Run-on Sentence Examples

Let’s go ahead and look at some examples:

I will run the race I will win the race.


Here, we have two independent clauses incorrectly connected.

Clause One: I will run the race.
Clause Two: I will win the race.


We’ll look at examples of corrections that use each of our three ways for fixing a run-on sentence.

Correction with semicolon: I will run the race; I will win the race.
Correction with conjunction: I will run the race, and I will win the race.
Correction with end punctuation: I will run the race. I will win the race.


Comma Splice

A type of run-on sentence you’ll have to work harder to catch is the infamous comma splice. A comma splice occurs when two or more independent clauses are connected only by commas.

Here’s an example:

I will run the race, I will win the race.


Comma splices can be easily fixed by adding a conjunction behind the comma and before the next main clause begins, by adding a semicolon instead of a comma, or by simply turning each clause into its own sentence.

Thanks for watching! Until next time!

Frequently Asked Questions


What is a sentence fragment?


A sentence fragment is an incomplete thought. In other words, it is a phrase or clause that is missing a main subject or verb. Here are a few sentence fragment examples:

“Climbed up the mountain”
“Before the storm rolls in”
“The large black bear”


How do you fix a fragmented sentence?


There are a few things you can do to fix a fragmented sentence. You can try attaching the fragmented sentence to another complete sentence in the text; determine what is missing from the sentence, then add whatever the sentence needs, such as a subject, verb, or direct object; or completely rewrite the sentence to make it a complete thought.


What is a run-on sentence?


A run-on sentence usually consists of two or more independent clauses that are not joined correctly. Here are a few examples:

“He ran the experiment for several hours and he didn’t see any results and so he went back to the drawing board and he came up with another experiment.”

“The leaves began to fall from the trees, it was starting to look more and more like autumn.”


How do you fix a run-on sentence?


Run-on sentences are often fixed by adding punctuation and conjunctions to break up the sentences. Take the following run-on sentence for example:

Run-on: “Hila likes green apples but she prefers red apples and Ollie likes green apples too.”

Fixed: “Hila likes green apples, but she prefers red apples. Ollie also likes green apples.”


How do you avoid run-on sentences?


Avoid run-on sentences by utilizing commas, semicolons, conjunctions, and periods to break up sentences.


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by Mometrix Test Preparation | This Page Last Updated: July 27, 2023

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