Spice Bazaar in Istanbul
In our second installment on comma usage, we are spicing it up. And by “it” I mean our sentences. Often authors are looking for ways to add a little more detail, a little more information, and a little more context to their sentences. They use introductory words, prepositional phrases, appositives, and other modifying phrases to spice up a sentence. By doing so, authors can avoid writing more sentences and it allows them to vary the rhythm and structure of their writing. When spicing up sentences in this way, commas play an important role.
Go to first installment for more examples: ”Comma Usage: Connector and Separator“
Commas with nonrestrictive (nonessential) words and phrases
Use commas to surround nonessential elements in your sentence. The idea behind this rule is straightforward enough: put a comma at the beginning and at the end of your nonessential information. But how do you know if the word group is essential or nonessential, restrictive or nonrestrictive?
This is one of those times in grammar and punctuation that the choice falls to the author. You must decide if the information you are providing is “restricting” the meaning of something so that your reader doesn’t confuse it with something else, or if the information you are providing is “nonrestrictive” and merely adds more information to the sentence.
Try this as a test: remove the phrase or words from your sentence. Does it change the meaning? Does the sentence now apply to something more general? If you answered yes, you found essential, restrictive elements in your sentence, and thus no need to use commas. But, if nothing really changes and your meaning is essentially unchanged, except that their might be a little less information in the sentence, you have found nonrestrictive, nonessential elements.
Let’s look at an example of a restrictive use and a nonrestrictive use of the phrase, “who are over the age of seventy”.
Seniors who are over the age of seventy are required to retake the driving test and eye examine before renewing their driving licence.
In the previous example, removing the phrase, “who are over the age of seventy,” would alter the meaning of “seniors.” Right now, the phrase is restricting the meaning of seniors to a select group–the ones over seventy–which is necessary for the meaning of the sentence to be clear. Thus the content of the sentence, and ultimately the author’s choice, dictate the use of commas.
Those two, who are over the age of seventy, meet at the cafe every morning to play chess.
In this second example, the phrase is surrounded by commas. Try removing the phrase from the sentence. Does the meaning remain intact? Essentially, yes, it remains the same. Although it might be a little more difficult to discern which two people the author is talking about, the phrase does not narrow or define something in the sentence. It is not essential for understanding the ideas conveyed. As such, the author used a comma before and after the phrase.
In addition, the words “that” and “which” can both be used to start phrases and clauses. As a general rule, use “that” with phrases and clauses that are essential to the meaning of your sentence, and use “which” with phrases and clauses that are not essential to the sentence. This is why a comma is used before “which” but not before “that”.
Comma with introductions
After introductory words and word groups, use a comma–just like in this sentence. There are many occasions when an author needs to preface the main content of the sentence with some information. That information can be a transition word or a phrase that clarifies the time or place of the content in the sentence. Sometimes the introduction is a subordinate clause that is helping to convey information about the main clause. Whatever the case, use a comma at the end the introduction.
WORD: However, she hasn’t been to work in a week, and I am starting to worry.
If a introductory word occurs in the middle of the sentence, make sure to surround the word with commas:
WORD: She hasn’t been to work in a week, however, and I am starting to worry.
PHRASE: In the summer of 1816, a “dry fog” hung over the northeastern United States dimming the sun allowing observers to see sun spots.
CLAUSE: Since farmers did not know the benefits of rotating crops in their fields, many farms went fallow due to a lack of nutrients in the soil.
Commas with parenthetical statements, contrasts, and asides
Authors like to include little asides, contrasts, and parenthetical information in sentences. This is information that interrupts the flow of the sentence, but does not change the essential meaning of the sentence. The reasons for adding information are numerous, but in all cases, commas are used to set off the information from the rest of the sentence.
After a long fall, and the winter wasn’t any shorter, the spring finally descended on Cape Cod bringing the first tourists and vacationers.
The simplest ice cream is made with dairy, sugar, egg, not by freezing cream.
Comma with tag sentences and direct address
A tag sentence is usually a question added to the end of a sentence. These tag sentences prompt the reader for a response or convey other information.
We should leave, shouldn’t we?
The package of ice cream will arrive today, I hope.
I think the solutions is a prime number, right?
Direct address refers to times when a person is directly addressed by name or when a group is addressed by name. In these cases, you will need to use commas to set off the direct address from the rest of the sentence.
Brothers and sisters, we are gathered here today to remember our friend who has passed from this life into the next.
You will receive our decision, Gillian, later in the week.
Jeremy, my friend, you are too late for dinner, but just in time for ice cream.
Return next Tuesday for more rules on common usage. If you can’t wait until then, check out another article about commas: “Comma Usage: Connector and Separator.”