I find myself often in writing using too many commas, but then going through and editing many of them back out again or restructuring to use full-stops.
Is there a rule of thumb I've forgotten from my school days (English language was never pushed very hard beyond first-school) that would help me decide when a comma is appropriate?
If you're using commas where they shouldn't be, they should obviously be removed.
One less common example of the misuse of a comma that might happen is comma splicing - using commas to join two independent clauses and create a run-on sentence. It happens like this, sometimes you miss it because it looks like an subordinate clause.
However, sometimes all the commas do belong where they are and yet it still feels like too much. Usually it's a case of this:
I think that situations such as this one, where there are lots of nested parenthetical, but still grammatically discernible, phrases, are the issue, as far as I know, where most people have the most trouble with the use of commas, because, because of all that nesting, they tend to take a lot more mental accounting to parse. Usually, in cases like that, in order to avoid comma overuse, the solution is to reword the sentence to make the phrase more direct and decipherable.
As far as I know, the issue where people have the most trouble with the use of commas is in situations such as the above where there are lots of nested parenthetical phrases that are still grammatically discernible but take a lot more mental accounting to parse because of all that nesting. Usually the solution in cases like that is to reword the sentence to reduce comma usage and make the phrase more direct and decipherable.
In other words, if you have too many commas, usually it's not the commas themselves that are the problem. Look at your sentence structure and see if you're taking yourself for loops while reading it.
How many commas is too many?
When they're incorrectly used. There are four principal uses for a comma –
As a listing comma in replace of words such as and, or etc.
As a joining comma in joining two sentences together with and, or etc.
As a gapping comma to show that words have been removed instead of repeated.
As a bracketing (or isolating) comma to mark off a weak interruption of the sentence so the sentence flows more smoothly.
It's worth taking time to understand how these four main comma uses are used and in doing so it will help you remove all the unnecessary or incorrectly used ones.
I like to say that much of the time when people use a comma, they really just want to use a period but don't know it. Elmore Leonard says that an exclamation point should not be used more than once per hundred thousand characters; I feel a similar rule should exist for commas. But, of course, Elmore Leonard doesn't make the rules and neither do I (fortunately). And I've already used three commas in this paragraph. What gives?
I'm going to make a big assumption here that you are using commas where they legitimately belong (http://www.grammarbook.com/punctuation/commas.asp). I am going to make the even bigger assumption that you are in fact using commas to elongate your sentences, to make them complicated, to have them drag out well past their usefulness; and that you want them to stop, but you aren't sure how to do it...
Many people feel that complex sentences somehow infuse their writing with more edge or depth. That long, lustrous sentences make your writing seem smarter. But commas are just a tool. They can only do what they are told, whether for the better or worse of a sentence.
If you feel you have too many commas, you do. In places that are appropriate, make them separate sentences. The worse that can happen is that you cut it back too far, you can see that you have cut it back too far, and you put some of the commas back.
There are some generally accepted style rules about commas in lists but in terms of overuse, I think it sensible to consider how commas can help you to write in a natural style that sounds more like the ebb and flow of speech. I believe commas were first introduced to show where to take a breath and if you don't use any it sounds like you are just babbling on and on and at some point you might even start to sound like a legal document that has been drafted to have no ambiguity or even worse an 'empty vessel'.
I don't think short sentences are always the best answer. Some do. In contrast, sensitive punctuation introduces a human feel to the prose - as if you are hearing a musical conversation, rather than just reporting the facts. You cannot easily indicate pitch and tone, so you have to do the best you can with words and punctuation.
In my opinion, the commonest problems are: lack of consistency, poor style, and little empathy for the reader. I find it particularly frustrating to read anything by an author who doesn't quite know what a comma is supposed to be doing in the sentence. It interrupts my train of thought when I spot a superfluous or missing comma; semicolons are another matter entirely. I assume I am not alone.
I value the comma but a good rule-of-thumb is to cut down on superfluous commas preceding 'and', 'but', and 'or'. However, the effect of an extra pause might be crucial to create the right feel, good timing, and clarity.
If you need examples of why the humble comma cannot be discarded, do also take a look at the 'Oxford comma' (aka Harvard comma).
I don't think there's any simple metric. Like, no one can say you should have twenty-seven commas per page or anything like that.
The first question would be, Do you have commas in inappropriate places? If you have sentences like, "Bob walked, to, the store, slowly" then yes, there are too many commas. But a sentence that contains a list could legitimately have many commas. Like, "He found a bottle, three coins, two keys, a small metal box, a pack of matches, some scraps of paper, and a patridge in a pear tree."
The real problem is not the number of commas per se, but whether they are being used properly. If they are, then I wouldn't even think about it.
If you think you have too many commas, and they are all used appropriately, it may be that your problem is that your sentences are too complex. If you have too many clauses in each sentence that can indirectly result in too many commas.
As Tylerhams said in a comment, perhaps if you gave a couple of sample sentences folks here could give a more specific reply.
The answer is, that there is no fixed number; it depends on context, style, and readership; a similar situation pertains to the semicolon, although the use of semicolons is out of fashion, in this age of diminished attention span; and, above all, it is a matter of intelligibility.
There's a lot of bullshit written about commas. A lot of hacks like Strunk and White have tried to make money by inventing rules that have no basis in what previous writers have done, or what makes sense, or how language actually works. (This is what a leading linguist, Geoffrey K. Pullum, someone who actually understands language, thinks of Strunk and White and other usage books: "untruths", "foolish assertions".) There are no rules. I can suggest a couple of principles, but feel free to ignore where it seems appropriate.
This is a good rule if you're worried about parentheticals and adverbs and the like. Consider the doubtful "Actually, I'm not sure about that" vs the firm "Actually I'm sure about that".
Pauses are often used to divide up sentences or utterances, and commas can be used likewise. Even when joining sentences you may or may not insert a pause: "I went to the hotel, but I'm not sure why." "I went to the park but I didn't take the dog."
If it is a longer pause, or the end of a sentence, then probably don't use a comma. If it's the end of a thought, use a full stop (unless another punctuation mark seems called for). If you're not sure, you might use a semicolon, but lots of people hate semicolons so you could probably use a comma. A lot of this is style, or taste.
Example: in general usage, "Bring me, Jenny" means "Take me along with you" addressed to someone called Jenny, while "Bring me Jenny" means "Bring the person called Jenny to me". Use the expected comma here, to avoid confusing your reader.
On the other hand, feel free to violate convention if you want to surprise your reader.
You use commas to be grammatically correct or for cadence purposes. The only time there are too many commas is when there are commas where there shouldn't be.
You can get away with not using a comma when you should; it's not going to bother the reader.
Example: Tyson called Jill and Tyler went to the store.
^^^That's grammatically incorrect, but your readers won't care.
Using commas out of place will cause a problem. A misplaced comma can make an otherwise normal sentence awkward to read. Your reader will care about that. Awkward sentences throw readers out of the story. And most of the time, if not 100% of the time, the comma is misplaced because it's used incorrectly (grammatical error).
