If commas were edible, no one need ever go hungry. You don’t necessarily see them everywhere in professional writing, but trust me when I say that less seasoned writers’ writing is teeming with commas. People feel an overwhelming need to stick them anywhere and everywhere when writing without really knowing why.
Let’s look at restrictive and nonrestrictive clauses, for example. One comma is all that distinguishes a restrictive from a nonrestrictive clause and you could potentially be signaling to your reader that you want your clause to be restrictive when you actually don’t, and vice versa.
Also called essential and nonessential clauses, they indicate to your reader what information in your sentence is vital to its meaning and what information is just extra, and can be ignored. To understand why correctly punctuating these clauses is important in your writing, think about taking notes at school or at a meeting. A competent note-taker knows not to transcribe every word that comes out of the speaker’s mouth. As entertaining as any tangents may be, only the most important information gets written down and studied. This editing of unimportant information keeps us sane; it’s simply impossible to commit everything to memory.
Restrictive and Nonrestrictive Clauses
A restrictive clause modifies a noun in a sentence and indicates that the information it contains is vital to the meaning of the sentence. It is not set off by commas. Here’s an example to help make this idea clearer:
The cat that has a crooked tail would rather play with rats than eat them.
The clause “that has a crooked tail” lets us know which cat out of all the possible cats in this world is the one that refuses to hunt rats. If you put commas around the clause, you make it nonrestrictive and dispensable. I like to use my thumb to cover the clause and see if the sentence retains its original meaning without it.
This next sentence has another restrictive clause. Try covering it up and seeing if the sentence still makes sense without it.
Alanis Morissette’s hit album Jagged Little Pill won a Grammy.
I’m calling the phrase “Jagged Little Pill” a restrictive clause because it limits the meaning of “hit album.” Students tend to want to put commas around titles without realizing that that makes them nonessential to the sentence. Without the title, you have no idea which album won a Grammy.
If we add some more identifying information, then enclosing the title in commas and thus making it nonrestrictive is perfectly acceptable.
Alanis Morissette’s hit album, Jagged Little Pill, won a Grammy in 1996.
Since Jagged Little Pill was the only one of Alanis Morissette’s albums to receive a Grammy that year, removing the title from the sentence now does not destroy the meaning. Now it’s time to look at nonrestrictive clauses.
A nonrestrictive clause also modifies a noun in a sentence and indicates that the information it contains is not essential to the meaning of the sentence. It is set off by commas. The following sentence contains a nonrestrictive clause:
Management rewarded the employees, who received bonuses.
This sentence has the nonrestrictive clause “who received bonuses.” It is nonrestrictive because it is set off by a comma. The sentence therefore means that ALL employees were rewarded.
If the comma were removed, the sentence would look like this:
Management rewarded the employees who received bonuses.
Without the comma the clause becomes restrictive. The meaning of the sentence changes as a result and now means that ONLY employees who received a bonus will be rewarded.
The difference between a restrictive and nonrestrictive clause is a difficult one for many people to grasp and only a good deal of practice will tighten your grasp on when to employ commas.
ChompChomp has a great explanation of essential and nonessential clauses that includes many more examples.
The Law Student’s Guide to Good Writing by Professor Grinker also contains a very thorough explanation of restrictive and nonrestrictive clauses.
I’ll keep updating this post with more examples of correct and incorrect usage as I see them in student papers. In time, I’d like to create worksheets to help with this grammar issue as there is a lack of practice for essential and nonessential clauses online.
Hope this helps your writing and keep practicing!
Photo credit: Cmurtaugh