Fixing Run-on Sentences (With Definition and Examples!)

Did you receive your essay back with the phrase, “Too many run-on sentences!” but no additional information on how to fix them? Well, you are in luck because we’ll teach you what run-on sentences are and how to fix them! 

Run-on Sentences: What Are They?

The short answer is that a run-on sentence has too many independent clauses without proper punctuation. It can occur when: 

  • Mixing up adverbial conjunctions with coordinating conjunctions. 
  • Not understanding the rules of commas and semicolons. 
  • Having too many clauses strung together. 

Let’s look more specifically at some of the most common reasons for run-on sentences:

Comma Splices

This kind of run-on sentence occurs when the writer attempts to join two clauses using a comma when it should be a semicolon, period, or comma with a coordinating conjunction.

Commas are not strong enough to link clauses together on their own; they need a little help. 

Here’s an example of a run-on sentence because of a comma splice:

"An independent clause makes sense on its own, it can be joined with a subordinate clause to form a complex sentence." 

Fused Sentences

A fused sentence occurs when multiple clauses are linked together without punctuation marks. It typically happens when the writer isn’t familiar with or isn’t paying close attention to their subjects and predicates and loses track of their independent clauses.

 Here’s an example of a fused sentence with two independent clauses:

"The subject of the sentence always comes before the predicate it is the main idea of the sentence."

 In that example, between the words “predicate” and “it” is where the clauses should be separated. 


This type of run-on occurs when too many conjunctions are used in a row. Typically speaking, you should only use one instance of coordinating conjunction to link two clauses together. Having more than that creates a run-on.

Here’s an example:

"Your punctuation may be correct, and you use commas with your coordinating conjunctions to link your clauses, but too many in one sentence without a period creates a problem, and your sentence seems to never end."

 In the sentence above, there are four total independent clauses linked together. Even though the commas and conjunctions are in the right places, there are too many for it to be grammatically correct.

Run-on Sentence Examples:

Take a closer look at the following examples of run-on sentences.

This sentence is a run-on it has two independent clauses and no punctuation between them. (fused sentence)
This sentence is a run-on, it doesn't have the correct punctuation between the independent clauses. (comma splice)
This sentence is a run-on, and it has too many independent clauses, and even though the commas are followed by a coordinating conjunction, it has more than two. (polysyndeton)
This sentence is a run-on and it is missing a comma between the first clause and the coordinating conjunction. (improper punctuation)

Four Ways to Correct Run-on Sentences

Now that you know how to identify a run-on, the next step is learning how to correct them. 

The first thing you’ll need to know is how to identify independent clauses, subordinate (sometimes referred to as dependent clauses), and fragments. 

All clauses (independent and dependent) will have a subject and a predicate. The difference is that independent clauses are grammatically correct on their own. On the other hand, subordinate clauses will always start with a subordinating conjunction and need to be connected with an independent clause to form a complete sentence. 

A sentence fragment is a group of words with a missing subject and/or a predicate.

Once you’re confident in the difference between the three, learning how to write and punctuate sentences properly comes down to knowing what your options are:

Method #1: Divide the Clauses With a Period

The simplest way to fix a run-on sentence is to divide it into separate sentences. 

You just add a period after the first independent clause and capitalize the first word of the second clause. Using this method, you’ll want to be sure to get rid of any coordinating conjunctions in the second clause. Take a look at the following examples:

IncorrectSeparating two independent clauses is easy. And you can do it!
CorrectSeparating two independent clauses is easy. You can do it!
Incorrect:These clauses are separated by a comma splice, the comma isn’t strong enough on its own.
Correct:These clauses were separated by a comma splice. The comma isn’t strong enough on its own.

 Method #2: Insert a Comma With a Coordinating Conjunction

 Sometimes instead of creating two separate sentences, it may make your writing flow better if you use a comma and a coordinating conjunction to combine the clauses. 

Tip: Use the acronym FANBOYS to remember which words are coordinating conjunctions. It stands for: 

  • For
  • And
  • Nor
  • But
  • Or
  • Yet
  • So. 

When linking clauses together to create compound or compound-complex sentences, these are all the options you have. Take a look at these examples:

Incorrect:When creating compound sentences, you need to pay attention to the punctuation and you shouldn’t forget the comma.
CorrectWhen creating compound sentences, you need to pay attention to the punctuation, and you shouldn’t forget the comma.
Incorrect:Comma placement is tricky but, it’s easy once you know.
CorrectComma placement is tricky, but it’s easy once you know.

Method #3: Put a Subordinating Conjunction

Subordinating conjunction creates a subordinate clause. A subordinate clause still has a subject and predicate, but it doesn’t make sense on its own. That’s why it functions as nouns, adjectives, or adverbs. 

Tip: Subordinate clauses cannot be left on their own; they are dependent on an independent clause to form a complete sentence. 

When using a subordinate clause at the beginning of a sentence, you add a comma after the clause. No comma is needed if the subordinate clause follows an independent clause. 

Incorrect:My teacher told me to never use the word “because” to start a sentence, because most people don’t do it correctly.
Correct:My teacher told me to never use the word “because” to start a sentence because most people don’t do it correctly.
Correct:Because most people don’t do it correctly, my teacher told me to never use the word “because” to start a sentence.

Method #4: Add a Semicolon

You can also replace the comma and coordinating conjunction with a semicolon. 

Tip: When using a semicolon, you don’t use coordinating conjunction. You should also ensure that there is an independent clause on both sides of the semicolon and not a fragment. 

A semicolon can be helpful when joining clauses that relate to each other; it helps your writing flow nicely by connecting and expanding on similar ideas.

Incorrect:You don’t need a conjunction when using a semicolon; because they’re strong enough on their own.
CorrectYou don’t need a conjunction when using a semicolon; they’re strong enough on their own.
Incorrect:Be sure each clause separated by a semicolon is a complete sentence; not a fragment.
CorrectBe sure each clause separated by a semicolon is a complete sentence; a fragment would be incorrect.

Now You Can Run On With This Knowledge

Remember, run-on sentences are sentences with too many independent clauses that are joined incorrectly. It can be because the punctuation isn’t correct or there are too many clauses in one sentence. 

This post was proofread by Grammarly. Try it - it's FREE!

Capitalize My Title is a dynamic title capitalization tool used to make sure your titles or headlines use proper capitalization rules according to various style guides include APA, AP, MLA, and Chicago. It also counts your words and checks for grammar issues.


Please enter your comment!
Please enter your name here