To be such a tiny thing, the comma has been known to cause frustration in the life of the writer. If you can relate to that, read on; this article will cover the use of the serial comma, and fixing comma splices and run-on sentences. Fixing Run-On Sentences Run-on sentences (also called fused sentences) are sentences that have two or more independent clauses that are not properly joined. An independent clause is one that has a subject and a verb and, thus, forms a complete thought. "Is ...