By Dr. Henry Price

External clues often alert us that all isn’t well as far as our economic development is concerned. Industries look elsewhere for new sites; unemployment is higher than in the rest of the Southeast; the “hum” of healthy business is missing.

In the same way, people use external information to judge the quality of your product. Your communication with the public and with your clients is revealing to even the most casual observer. Something as simple as a comma says a lot.

Commas are very small things, but they are powerful — like a stick of dynamite — and they can drastically, and often embarrassingly, alter the meaning of a sentence if they aren’t used properly.

Take this sentence as an example: “He said that all of his affection was reserved for his wife, Susan.” If you use the comma after “wife,” the word “Susan” becomes an appositive. It means the same thing as the word it follows; therefore, the man has only one wife, and her name is Susan. Without the comma, the man has more than one wife, but he is talking about the one named Susan. If you don’t use the comma, you’re saying the man is a polygamist!

Here are the most important and most frequent reasons to use commas in sentences. Some require a bit of explanation.

1. Use a comma before the word “etc.” at the end of a series.

2. Use a comma after introductory words, clauses, or phrases. (Most style manuals tell you that you don’t have to use the comma if the word, clause, or phrase is a short one. Unfortunately, they don’t define “short.” Is it one word, two words, six words? If I can do a thing one way and always be correct or do it another way and perhaps be wrong, I’m going with the “always correct” way.)

3. Use a comma between two independent clauses joined by a conjunction to form a single sentence. (A clause is independent because it has its own subject and its own predicate. You can join two independent clauses with a coordinating conjunction. By far, the six most commonly used coordinating conjunctions are: and, or, nor, but, yet, for. They are all conjunctions, but if they are being used as coordinating conjunctions, they require a comma in front of them.)

4. Use commas around nonessential (nonrestrictive) words, phrases, or clauses. (They are considered nonessential or nonrestrictive because they can be taken out and the sentence still makes complete sense.)

5. Use a comma between coordinate adjectives — that is, if you can reverse the adjectives and put “and” between them. (The tall, red-haired woman entered the room.)

6. Use a comma before the adverbs “too,” “as well,” and “also” at the end of a sentence.

7. Use commas to set off a conjunctive adverb (such as however, likewise, at the same time, therefore) from the rest of the sentence.

8. Use a comma to set off a noun of direct address. (Helen, are you going to town?)

9. Use a comma before “not” when showing contrast.

And there you have it. It takes a little time to get the nine rules under control, but this is one of those places where time indeed does equal money because the quality of your written communications reflects heavily on the reader’s perception of the quality of your product.