Items in a Series
Many of us have agonized about whether to place a comma after the next-to-last item in a series, before the “and.” We’ve heard it’s a rule to put it in; we’ve also heard the rule dropped away, and the comma is not necessary.
Most current reference books, while not requiring this serial comma (also called the Oxford comma), strongly recommend using it, especially if the meaning would be unclear without it.
Example: The following positions are available: clerk, accountant, receptionist and statistical typist.
How many jobs are available? Three? Four? Without the comma, a reader might think that one person is being asked to perform the duties of receptionist and statistical typist. (Yes, of course, we can always rewrite it to make it even clearer.)
Example: The following positions are available: clerk, accountant, receptionist, and statistical typist.
Here, it’s easier to understand there are four jobs available.
Learning when to put a comma between two or more adjectives takes practice. There is a rule, but it’s not always easy to decide if it applies. The test is to see if “and” fits between the adjectives; if it does, logically and easily, the adjectives are coordinate. If you leave and out, you need a comma to take its place. This is not an absolute science, however; it’s possible to disagree about whether you would have used and in the first place.
Example: The old stone wall is crumbling.
Few of us would say it’s an old and stone wall. Most of us would say that stone wall is a compound noun and old modifies it; therefore, no comma is necessary.
Example: The dry, dirty ditch will be filled with water when it rains.
Here, most of us would probably say the dry and dirty ditch; a ditch could be dirty one week and clean the next. It’s unlikely anyone would call dirty ditch a compound noun.
The basic rule is this: If the title comes directly before the name and is used as a title, rather than as an occupation, use no comma to separate it from the person. If the title/occupation follows the name, use commas around it.
Remember, too, that titles may be more than one word. The test is trying to remove the name that follows. If you can’t, you don’t use commas. You can also substitute a one-word title such as Mr. or Ms.; would you ever write “Ms., Susan Brown is on vacation”? No, I didn’t think so. Multi-word titles are treated the same as single words would be.