The Tricks of Comma Usage
When it comes to your writing, there are inevitably grammatical concepts that will trip you up and cause confusion. Many instructors and translators often note that English grammar is one of the trickiest, due to an inherent lack of straightforward rules (with variations within the rules as well)!
However, punctuation usage can often be difficult as well, and the comma—often hailed as one of the easier punctuation marks to master—presents its own challenges.
Merriam-Webster defines the comma as both “a punctuation mark, used especially as a mark of separation within the sentence,” and a “pause” or “interval.” Needless to say, when reading any text, a comma is a strong indication that there is a brief pause.
Of course, there are numerous rules about comma implementation that serve as the fundamentals for use of the mark. These will be covered at the end of this article, albeit briefly. But to begin, let’s consider a straightforward, yet often misunderstood comma usage question. Take a look at the following statement:
Many people so often claim that commas are ‘reniform,’ but I wholeheartedly disagree.
For the scientist reading this, you’ll recognize that this essentially states that commas are kidney-shaped. That may or may not be true (potentially dependent on your preferred font); however, take a look at the comma usage. This, of course, is the intention of this article.
You will notice that within the single quotations there is a comma, and that comma is placed within the single quotations. This is arguably one of the trickier questions that people have surrounding comma usage (and punctuation more broadly as well). Still, it is easier than you might think. Comma implementation both inside and outside quotations can be correct in this example; however, if your audience/readers likely expect American English, those commas and periods belong within the quotes. For British English, the opposite is true.
As for the more fundamental rules, if you begin a sentence with a dependent clause, like “After I finished school,” a comma is necessary. A dependent clause is one that contains several elements of a proper sentence (e.g. verb and subject), but cannot act alone. Thus, a full sentence beginning with this dependent clause might state, “After I finished school, I ate a bag of chips.”
Another crucial implementation of comma usage is when you are listing a series of items. Read the following sentence and consider what is wrong:
John went to the supermarket and purchased bacon pancake mix milk and eggs.
Reading that might just give you the chills. Who wants to eat bacon pancake mix milk? However, those chills can be avoided with commas. The proper usage would be:
John went to the supermarket and purchased bacon, pancake mix, milk, and eggs.
Plentiful debate surrounds that final comma, which some claim is unnecessary. Still, as a general rule of thumb, not including this final mark has the potential to create confusion for readers.
Of course, the world of commas (and English punctuation more broadly) has far more restrictions and guidelines, best left for another day. These include the infamous ‘comma splice,’ among others. But have no fear! I'll keep you posted on other details to look out for in the coming weeks.