The comma splice is the most common error people make with this punctuation mark, but surprisingly few people have even heard of it. Which is perhaps why it’s so common…hmmm?
Anyway, once you know what it is, you’ll start seeing it everywhere.
Comma splicing is basically when you try and stick two sentences (or independent clauses)together with a comma.
Commas separate clauses. They aren’t sticky, so you can’t use them to stick sentences together. For example:
The adult human brain weighs two to three pounds, it looks like a cauliflower.
The sentence above is spliced. To correct it, you have a number of options:
Option #1: Add a joining word like and, but, so, yet or for.
The adult human brain weighs two to three pounds, and it looks like a cauliflower.
Option #2: Use a full stop (period).
The adult human brain weighs two to three pounds. It looks like a cauliflower.
Option #3: Use a semicolon.
The adult human brain weighs two to three pound; it looks like a cauliflower.
OK, so that’s it for the most common error you’re likely to make with commas, but it’s not the only one. Here’s more on what else you need to know about commas (you may be surprised!)