As we’ve discussed before, commas can be tricky. Even expert writers often forget to place commas where they’re needed or place an extra comma where it wasn’t needed. One of the most common comma mistakes is when one is inserted in a sentence to separate two actions being performed by one subject. For example:
Incorrect: Boris picked up his knife, and finally began to carve.
Correct: Boris picked up his knife and finally began to carve.
|Good for you, Boris.|
I see this all the time. I think these commas often occur because writers mentally narrate to themselves as they write and feel like they need a comma wherever their mental narration pauses or hesitates. After all, when people read out loud, they often pause slightly on commas. Read that last sentence out loud—you instinctively pause on the commas, don’t you? It’s just a slight hesitation, but it’s there.
But not every hesitation requires a comma. In the case of our example sentence, we have one subject—Boris—performing two sequential actions, and the actions are separated by “and.” In this sort of situation, you do not need to use a comma. Not ever. When you’re writing dialog, it may be tempting to include a comma to indicate a hesitation, but I recommend against it. How important is that brief hesitation, anyway? If it’s not pronounced enough to justify using ellipses, then it’s not important enough to require a comma.
Now, some people like to say that you should never use a comma when the word and is used to combine to actions or phrases. That’s not true. But when both actions are performed by the same subject, this will generally be the case.