The Comma Splice
Unfortunately, since commas are commonplace, they are also used incorrectly quite often. One such error is called a comma splice, which occurs when a comma is incorrectly inserted between two independent clauses. Remember, an independent clause is one that has a subject and predicate and can stand alone as a full sentence. Look at the following examples:
- Nocturnal-Flying-Rodent Man was the savior of the city.
- He defeated the evil Puzzler.
These are two full sentences, each with a subject and a predicate. If we were to connect these independent clauses without any punctuation, it would be a run-on sentence.
- Nocturnal-Flying-Rodent Man was the savior of the city he defeated the evil Puzzler.
Many will notice they need punctuation to separate the two clauses, but most will simply insert a comma and be done with it. This is a comma splice.
- Nocturnal-Flying-Rodent Man was the savior of the city, he defeated the evil Puzzler.
The comma alone cannot fix the run-on sentence. This example is wrong! Let's look at the three methods you can use to correct a comma splice.
The Period New Sentence Fix
The first method is also the simplest. If you have two independent clauses that can stand alone, why not separate them completely? Do so by inserting a period, which indicates the end of a sentence, and then, capitalize the first word to begin a second sentence.
- Nocturnal-Flying-Rodent Man was the savior of the city. He defeated the evil Puzzler.
This method clearly shows two independent clauses with proper punctuation.
The Semicolon Fix
Perhaps you realize your comma splice error, but you still want to show that the two clauses are connected. There is punctuation that can indicate a close relationship. The semicolon is used to separate independent clauses, while at the same time, showing they are related. To use a semicolon, insert it where the period would be, but do not capitalize the second clause.
- Nocturnal-Flying-Rodent Man was the savior of the city; he defeated the evil Puzzler.
Especially since we have the pronoun 'he,' which refers to the 'Nocturnal-Flying-Rodent Man,' using the semicolon keeps the close relationship between the two clauses intact.
The Conjunctions and Subordinators Fix
The final method for fixing comma splices actually does involve the comma! However, the comma cannot be inserted alone. You must insert a comma and a conjunction, which is a connecting word. 'And,' 'but,' 'or,' and 'so' are all examples of conjunctions. To use this method, insert a comma after the first independent clause with a conjunction immediately following.
- Nocturnal-Flying-Rodent Man was the savior of the city, and he defeated the evil Puzzler.
You can also insert a subordinator with a comma to fix a comma splice. Think of subordinators as conjunctions that make one clause dependent. 'While,' 'because,' 'before,' 'when,' and 'since' are all subordinators. Subordinators can come at the beginning of the sentence or between the clauses.
- Since Nocturnal-Flying-Rodent Man was the savior of the city, he defeated the evil Puzzler.
Look how adding the subordinator 'since' changed the first clause to a dependent one, because it can no longer stand alone. 'Since Nocturnal-Flying-Rodent Man was the savior of the city' is not a full sentence. Also, note how the subordinator was at the beginning of the sentence, but the comma remained in between the two clauses. No matter where you insert the subordinator, be sure to insert the comma in between the clauses.
Adding a comma and either a conjunction or a subordinator is a perfect way to connect clauses while keeping specific relationships clear.
Lesson Summary
To review, the comma is a punctuation mark that indicates pauses between parts of a sentence. The comma is part of a grammatical error called the comma splice, which occurs when a comma is incorrectly inserted between two independent clauses. An independent clause is a sentence that has a subject and a predicate and can stand alone as a full sentence. You can't just remove the comma in this situation, though. That would create a run-on sentence, which is connecting two independent clauses without punctuation. Instead, to fix this error, choose one of these methods:
- Insert a period (indicates the end of a sentence), and begin a new sentence.
- Insert a semicolon (used to separate independent clauses while at the same time showing they are related).
- Insert a conjunction (a connecting word) or a subordinator (conjunctions that make one clause dependent) along with the comma.