A comma splice contains two or more complete thoughts with a comma between them.
The tax referendum failed to pass in the last election, it will be on the ballot again.
The comma signals a short pause, but it is not a strong enough punctuation mark to separate two complete thoughts. You can correct a comma splice in one of three ways:
1. Use end punctuation to separate the two thoughts into two sentences. Capitalize the first word of the second sentence.
The tax referendum failed to pass in the last election. It will be on the ballot again.
2. Join the two thoughts by replacing the comma with a semicolon, which shows that the two thoughts are related.
The tax referendum failed to pass in the last election; it will be on the ballot again.
3. Add a conjunction, such as and, but, or, nor, for, so, or yet, after the comma.
The tax referendum failed to pass in the last election, but it will be on the ballot again.