You probably remember the terms “comma splice” and “fused sentence” (also called a comma fault and run-on sentence, respectively) from some point in English class. For those of you who need a refresher, these terms refer to sentences in which two independent clauses have been improperly linked.

What’s an independent clause? It’s a group of words that include a subject and verb and can stand alone as a sentence because the words express a complete thought. Independent clauses can also form parts of a sentence. For example, there are two independent clauses below:

The project is behind schedule.
Our communications team has to work late.

Each of these two clauses express a complete thought, but you probably can see the flow of logic that would allow for them to be connected in one sentence. It’s a matter of connecting them properly.

Here’s Your Problem:

Fused Sentence
In a fused sentence, two independent clauses are simply thrown together in a sentence without any punctuation or connectors. In such an instance, our two example clauses would look like this:

The project is behind schedule our communications team has to work late.

Comma Splice
When the two independent clauses are connected by only a comma, the sentence now has a comma splice as in the example below:

The project is behind schedule, our communications team has to work late.

Repair Options:
To fix a comma splice or fused sentence, use one of the three options below.

1. Use a Coordinating Conjunction + a Comma

When you use a comma to connect two independent clauses, it should be accompanied by one of the seven coordinating conjunctions (and, but, for, nor, yet, or, so). So the sentence should look like this:

The project is behind schedule, so our communications team has to work late.

or

The project is behind schedule, and our communications team has to work late.

2. Use a Semicolon

While a comma needs the support of coordinating conjunctions, a semicolon is considered strong enough mark to link two independent clauses all on its own. However, semicolons ramp up the drama of the sentence by a few degrees, so it is best to use them sparingly.

The project is behind schedule; our communications team has to work late.

3. Use a Period

Since comma splices and fused sentences contain two independent clauses, you can always add a period at the end of the first clause, insert a space, and begin the second clause with a capital letter. That is, break the sentence in two:

The project is behind schedule. Our communications team has to work late.

Recognizing structural flaws in your sentences while you’re busy writing or even revising can be challenging, especially if you’re in a rush. You can become more familiar with these types of flaws via these online quizzes for comma splices as well as run-on sentences. Even if you’re a seasoned professional, an occasional review keeps your skills sharp and makes spotting errors a quicker, easier process.