24.3: Comma Splices

One of the most common sentence level errors in college writing, a comma splice occurs when you connect two complete sentences with only a comma (as opposed to a comma and a coordinating conjunction, or a semicolon). Two examples follow:

I enrolled early, I had my pick of classes.

Dorotea had no one with whom to share her thoughts, she lived alone in a nearlyruined house. (from Elena Garro, Los recuerdos del provenir [Remembrances of Things to Come], translated by John Buaas)

In these two sentences, we have two independent clauses joined with a comma but lacking the required connecting word. In American Standard English, a comma alone is considered too weak to hold together two independent clauses on its own.

Note the introductory phrase of the preceding sentence. In the standard practice of writers in the United Kingdom and the nations of the former British Commonwealth (such as India, Hong Kong, and many African and Middle Eastern nations), as well as in Spanish-speaking countries (Garro, the author of the second sentence, is from Mexico), sentences such as those you see above would be perfectly acceptable. Students educated overseas, or even students whose dominant language is American English but who grew up in Spanish-speaking households, will of course often produce writing that reflects those other conventions.

If this in some way describes you, the point here is not to tell you that what you have grown up with is suddenly “wrong”—it is simply to say that because American Standard English has a different set of assumptions in place regarding comma usage, you will have to be a bit more vigilant with regard to editing for comma usage. Fortunately, your instructors and tutors and the editors at the OWL are aware of these differences and will remind you gently of them, as well.

You have several different ways to fix comma splices, but they do not add up to the same result each time. Note how, in the sentences below, each approach subtly changes the relationship between the two clauses. As you grow from being a corrector of errors in your work to becoming a genuine editor of it, you will become alert to how you can be more precise in using these combinations to say in writing something closer to what you “see” in your mind regarding those relationships.

1) Add an appropriate coordinating conjunction after the comma

I enrolled early, so I had my pick of classes.

Dorotea had no one with whom to share her thoughts, for she lived alone in a nearly-ruined house.

2) Change the comma to a semicolon

I enrolled early; I had my pick of classes.

Dorotea had no one with whom to share her thoughts; she lived alone in a nearlyruined house.

3) Turn each sentence into an independent clause by changing the comma to a period

I enrolled early. I had my pick of classes.

Dorotea had no one with whom to share her thoughts. She lived alone in a nearlyruined house.

4) Make one of the clauses subordinate to the other and then join them

Because I enrolled early, I had my pick of classes.

Since Dorotea lived alone in a nearly-ruined house, she had no one with whom to share her thoughts.

Quick Reference: Coordination and Subordination

If you choose to use coordination or subordination, you can pull from the following lists of common coordinating and subordinating conjunctions. While these lists are not exhaustive, they provide you with a good starting point if you need to restructure your sentences.

Coordinating Conjunctions	Subordinating Conjunctions
For, and. nor, but, or, yet, so	After, although, as, as long as, because, before, besides, even if/even though, if/if only, in order to, now that, once, rather than, since, though, without, unless, until, when/whenever, where/wherever, whether, while, within

See this page about comma splices in professional writing from Business Insider. See this lesson for help with comma splices and run-ons from Khan Academy.

Exercise 24.3a: Correcting Comma Splices

Correct any comma splices you find in the following sentences.

1. Neuroscientists used to think the brain stopped changing when a person became an adult, this led to the idea that it was hard for adults to learn new skills or retain facts.
2. However, in the past three decades, neuroscientists have discovered that the brain is actually “massively plastic” through all stages of a human’s life, meaning it is just as easy to learn and gain new skills when a person becomes an adult.
3. The brain actually changes physically when a person learns a new skill, the brain of a piano player, for example, actually looks physically different from that of a person who doesn’t play an instrument.
4. Plasticity means that learning a new skill, such as learning how to type or drive, is difficult at first, once a person works at the new skill, however, it will become easier and the person will become better at the new skill.
5. This also applies to tasks we complete for school, for example, doing math or reading a textbook might be really difficult at the beginning of the semester, but the more you practice these skills, the easier they will become because the brain has changed to make these new skills second nature.

Exercise 24.3b: Correcting Comma Splices in Context

Identify and correct the comma splices in the following paragraph. When you’ve finished, write a paragraph reflecting on how the changes impacted the reading experience.

According to Carol Dweck, individuals can have a growth or fixed mindset, these two mindsets dictate a person’s opinion of learning and success. A person with a growth mindset will care more about improving at a task. The student with a growth mindset will learn more easily because they encounter a difficult concept and work to learn it, if the student struggles to learn the new concept, they will understand the struggle is just part of the learning process. In fact, the student might even embrace the difficulty because they see it as a sign that they are learning. However, a person with a fixed mindset cares more about succeeding than learning, if they are struggling to learn a new concept, the student with a fixed mindset will fear that they are not smart. The student with a fixed mindset would rather have an easier task that doesn’t teach them anything, whereas the student with a growth mindset would rather tackle a difficult task that they can learn from. Clearly, the person with a growth mindset will have an easier time with the coursework as it becomes more difficult. If you feel you have a fixed mindset, don’t worry, you can establish a growth mindset. One way to establish a growth mindset is by teaching yourself how the brain changes as it learns and understanding the learning process at the biological level, Carol Dweck also has other tips for changing your mindset in her essay, “The Mindsets."