A sentence fragment lacks at least one of the three features of a complete sentence: a subject, a verb, and/or a complete thought. As a result, the logical progression of your writing may be unclear, potentially confusing the reader. Although incomplete sentences are regularly used in creative writing and journalism, this sentence structure is too informal for academic writing, except in certain table and figure legends and brief summaries. Fragments lacking one or more of these three components may seem incomplete and are often due to a typographical error:
- Increased five-fold. This fragment lacks a subject.
- The transporter levels. This fragment lacks a verb.
- Such as HeLa and T2 cells. This fragment lacks a subject and a verb.
- The transporter levels were. This fragment lacks a complete thought.
- The transporter levels were. Increased five-fold. This fragment may be due to a typo.
- The transporter levels were increased five-fold in several cell lines, such as HeLa and T2 cells. This complete sentence has a subject, a verb, and a full thought.
Sentence fragments may be more difficult to identify when they consist of a dependent clause that has both a subject and a verb but cannot stand alone, as in the cases below:
- The insulin levels increased. Whereas the glucagon levels decreased.
- The insulin levels increased. And the glucagon levels decreased.
In both cases, each clause has a subject and a verb (“levels increased” and “levels decreased”). However, in both examples, the first sentences are complete thoughts, whereas the second sentences are incomplete because they begin with subordinating or coordinating conjunctions in the first and second examples, respectively. These conjunctions are used to link two independent clauses; if only one phrase is associated with a conjunction, the meaning of the sentence may be unclear. Both cases can be addressed by merging the complete and incomplete sentences and adding a comma:
- The insulin levels increased, whereas the glucagon levels decreased.
- The insulin levels increased, and the glucagon levels decreased.
The conjunctions now properly link the two independent clauses “The insulin levels increased” and “the glucagon levels decreased.” Alternatively, the fragments could be restructured into complete sentences by using transitions instead of conjunctions:
- The insulin levels increased. In contrast, the glucagon levels decreased.
- The insulin levels increased. Additionally, the glucagon levels decreased.
We hope that today's editing tip will help you to identify and repair sentence fragments in your writing. As always, please email us at [email protected] with any questions. We wish you the best in your research and writing endeavors!
