Run-on sentences: Overview

Run-on sentences are independent clauses that have not been joined correctly. When two independent clauses appear in one sentence, they must be joined in one of these ways:

• with a comma and a coordinating conjunction (and, but, or, nor, for, so, yet)
• with a semicolon (or occasionally with a colon or a dash)

When two independent clauses are not properly joined, the result is a run-on sentence.

Note:A run-on sentence is not necessarily a long or complicated sentence. A run-on is a specific kind of error in which the writer combines two independent clauses without appropriate punctuation.

There are two types of run-on sentences: fused sentences and comma splices.

Fused sentences

When a writer puts no mark of punctuation and no coordinating conjunction between independent clauses, the result is a fused sentence.

Comma splices

A more common type of run-on sentence is the comma splice—two or more independent clauses joined by a comma without a coordinating conjunction. In some comma splices, the comma appears alone.

In other comma splices, the comma is accompanied by a joining word that is not a coordinating conjunction. There are only seven coordinating conjunctions in English: and, but, or, nor, for, so, and yet.

However is a transitional expression, not a coordinating conjunction. Common transitional expressions are therefore, then, nevertheless, in fact.

The flowchart can help you review your writing for run-on sentences.

Transitional expressions

Recognizing run-on sentences

Exercises:

Run-on sentences 1

Run-on sentences 2

Run-on sentences 3

Run-on sentences 4

Run-on sentences 5

Run-on sentences 6