The Comma Splice

When you write, do you sometimes feel like you keep going on and on without knowing exactly where to end your sentences? These runaway passages may be comma splices.

The following sentence, written by a CLC student, really includes several sentences combined with commas. This is called a comma splice. In a comma splice, the writer uses commas to join thoughts together, but without a conjunction (and, but, or, etc.).

Sometimes I felt nostalgic when I remembered the town where my parents lived, there was a beautiful waterfall in the river, it is 12 feet high and 36 feet wide, many years ago one man made it on the side of the mountain for producing electricity.

Quick Challenge: Can you spot the complete ideas that are combined with commas in the passage above? Which commas separate complete sentences?

There are really four complete thoughts here.

  1. Sometimes I felt nostalgic when I remembered the town where my parents lived.
  2. There was a beautiful waterfall in the river.
  3. It is 12 feet high and 36 feet wide.
  4. Many years ago one man made it on the side of the mountain for producing electricity.

The writer has used commas to connect sentences where periods would have traditionally been used to separate the various complete thoughts.

!!! Note how the writer "hears" where the sentence boundaries are. The commas are consistently placed where a speaker would pause. All the writer has to do is use more powerful punctuation in the same places.


There are four basic ways to correct a comma splice. Find the comma that separates your two independent clauses and

  1. Replace the comma with a period,
  2. Replace the comma with a semicolon,
  3. Insert a conjunction after the comma, OR
  4. Make one of the independent clauses a dependent clause. Read on for details.

Examples of "More Powerful" Punctuation

Commas are too "weak" to separate two independent clauses. Perhaps the easiest way to correct a comma splice is to replace the comma with a period or semi-colon. These punctuation marks are stronger signals to readers that a new complete thought is coming up.

I woke up even before the alarm went off, I was too sad, depressed, and melancholy to sleep.

Quick Challenge 2: Find the comma that separates two independent clauses in the example above and change it to a period.

Now, what if you don't want a "stop" as strong as a period? After all, the second sentences in our example explains the first (it explains why the writer woke up early). This would give you a good reason to use a semi-colon:

I woke up even before the alarm went off; I was too sad, depressed, and melancholy to sleep.

!!! Note that if the word after the semi-colon is not a proper noun ("I" or a name), then it should not be capitalized.


Solutions that Focus on Relationship

Sometimes writers want to keep the ideas flowing together to show a relationship between them; therefore, they don't want to use a period or semi-colon. Another common way to correct a comma splice is to add words. The most basic way to do this is to insert a conjunction (and, but, or, etc.) after the comma.

Quick Challenge 3: Edit the following comma splice by adding an appropriate conjunction. Then compare your answer to the two possible solutions.

Some of these fears are helpful because they can motivate a person, other fears can prevent you from allowing yourself to experience something.

The second way to correct a comma splice by adding words is to change one of the two independent clauses to a dependent clause. Similar to the solution above, the writer must consider the relationship between the two complete ideas. Dependent clauses typically begin with words like although, because, since, and after (link to the Punctuation Pattern Sheet for more examples).

To make "I woke up even before the alarm went off; I was too sad, depressed, and melancholy to sleep" read even smoother, it may be revised to. . .

I woke up even before the alarm went off because I was too sad, depressed, and melancholy to sleep.



If you are a CLC student and would like more practice with comma splices, stop by the Writing Center and ask for an exercise. Or, if you prefer, request an exercise via email (writingcenter@clconline.clc.cc.il.us), and we'll send it to you as an email attachment. Please include your name and CLC course when writing to us.


L. Frega
CLC Writing Center