P3: Eliminating Comma Splices and Fused Sentences

LEARNING OBJECTIVES

  1. Use commas correctly in compound sentences.
  2. Use semicolons correctly in compound sentences.
  3. Recognize comma splices and fused sentences.

Two of the most common problems people have with compound sentences are comma splices and fused sentences. The key to understanding these problems is to recognize the possible compound sentence formats:

  1. two independent clauses separated with a comma and coordinating conjunction (and, but, so, for, nor, or, yet);
  2. two independent clauses separated with a semicolon by itself;
  3. two independent clauses separated with a semicolon and a conjunctive adverb (however, therefore, consequently, moreover, etc.), used to clarify a specific logical relationship between the two independent clauses.

The following video from Khan Academy explains how to spot comma splices and run-on or fused sentences:

“Run-ons and Comma Splices.” Published by Khan Academy.

Understanding and Avoiding Comma Splices

Two different situations can result in comma splices.

Examples

Problem: A comma joins independent clauses instead of the clauses being joined by a comma followed by a coordinating conjunction.

Example: Her name was Jean Louise Finch, she wanted everyone to call her “Scout.”

Correction: Her name was Jean Louise Finch, but she wanted everyone to call her “Scout.”

Problem: A comma joins two independent clauses when a semicolon should be used.

Example: Atticus didn’t want Scout to fight, however, she could not ignore injustices.

Correction: Atticus didn’t want Scout to fight; however, she could not ignore injustices.

Understanding and Avoiding Fused Sentences

A fused sentence is also called a run-on sentence and occurs when two independent clauses are joined without any punctuation.

Example

Mr. Cunningham is poor he cannot pay Atticus for legal services.

  • Correction option 1: Add a coordinating conjunction and a comma: Mr. Cunningham is poor, so he cannot pay Atticus for legal services.
  • Correction option 2: Place the independent clauses into two separate sentences: Mr. Cunningham is poor. He cannot pay Atticus for legal services.
  • Correction option 3: Place a semicolon between the two clauses: Mr. Cunningham is poor; he cannot pay Atticus for legal services.
  • Correction option 4: Place a semicolon between the two clauses, and use a conjunctive adverb for further clarification: Mr. Cunningham is poor; therefore, he cannot pay Atticus for his legal services.
  • Correction option #5: Turn one of the independent clauses into a dependent clause: Mr. Cunningham cannot pay Atticus for his legal services because he is poor.

OR

  • Because he is poor, Mr. Cunningham cannot pay Atticus for his legal services.

Adapted from Chapter 18 “Punctuation” in Writer’s Handbook v 1.0 used according to Creative Commons CC BY-NC-SA 3.0

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