In English grammar, nonessential modifiers play an important role in adding extra information to a sentence without changing its fundamental meaning. These modifiers, also known as nonrestrictive elements, can describe, explain, or add detail to a noun or verb. However, what makes them unique is that the sentence would still make sense if the modifier were removed. Because of this characteristic, nonessential modifiers are enclosed in specific punctuation marks to separate them from the rest of the sentence. Understanding how to properly use and punctuate nonessential modifiers helps improve clarity, grammar accuracy, and overall writing style.
What Are Nonessential Modifiers?
Nonessential modifiers are words, phrases, or clauses that add information but are not necessary to identify the subject or object of the sentence. If you remove a nonessential modifier, the core sentence still retains its meaning.
For example
My brother, who lives in Chicago, is visiting next week.
In this sentence, who lives in Chicago is a nonessential modifier. The sentence would still make sense if you removed it My brother is visiting next week. The extra detail is helpful, but it’s not required to understand the main point.
Nonessential Modifiers Are Enclosed In Commas
The most common punctuation used to enclose nonessential modifiers is the comma. When a modifier is nonessential, it is set off by commas on both sides to clearly separate it from the main part of the sentence.
Examples of Commas with Nonessential Modifiers
- My car, which is nearly ten years old, still runs well.
- The book, a bestseller last year, is being made into a movie.
- Samantha, our team captain, scored the winning goal.
In each of these examples, the phrase between the commas is not essential to the core meaning. The commas show that the sentence would still make sense without that extra information.
Other Punctuation Used with Nonessential Modifiers
While commas are most commonly used, there are other punctuation marks that can enclose nonessential modifiers, depending on style and emphasis. These include parentheses and em dashes.
Parentheses for Less Emphasis
When the nonessential information is considered less important or more of an aside, parentheses may be used.
- Her speech (which was quite inspiring) received a standing ovation.
- They visited Rome (their favorite city) before heading home.
Using parentheses gives the added detail a lower tone or background status. It feels less integrated into the main sentence than when commas are used.
Em Dashes for Stronger Emphasis
For dramatic or deliberate emphasis, em dashes can enclose nonessential modifiers. This punctuation draws the reader’s attention to the inserted phrase more than commas or parentheses.
- The teacher known for her strict rules cancelled the pop quiz.
- Our dog always excited for walks started barking at the door.
Em dashes highlight the inserted information and give it more impact, while still maintaining its nonessential nature.
How to Identify a Nonessential Modifier
It can sometimes be tricky to decide whether a modifier is essential or not. Here are a few ways to identify nonessential modifiers
- Ask if the sentence makes sense without the modifierIf it does, it’s likely nonessential.
- Check if it adds descriptive information rather than defining somethingNonessential modifiers describe but don’t identify.
- Look for relative clauses beginning with which or whoThese often introduce nonessential elements.
For example
The students who arrived early got front-row seats.
In this case, who arrived early is essential to the meaning. Not all students got front-row seats only those who arrived early. Removing the modifier would change the meaning, so it is essential and should not be enclosed in commas.
Essential vs. Nonessential Modifiers
Understanding the difference between essential and nonessential modifiers is critical for correct punctuation. Let’s compare the two
- Essential ModifierDefines or limits the meaning of a noun.
The man who owns the red car is my uncle.
(Who owns the red car is essential because it tells us which man.) - Nonessential ModifierAdds extra information that can be removed.
My uncle, who owns a red car, is visiting today.
(The fact that he owns a red car is extra; we already know who my uncle is.)
Use commas for nonessential modifiers and omit them for essential ones.
Common Types of Nonessential Modifiers
Nonessential modifiers come in different forms, including
Nonessential Appositives
An appositive is a noun or noun phrase that renames another noun. If it’s nonessential, it’s enclosed in commas.
- My sister, a talented artist, won the award.
Nonessential Participial Phrases
These begin with a verb ending in -ing or -ed and act like adjectives.
- The cat, purring loudly, curled up on the couch.
Nonessential Relative Clauses
Usually introduced by who, which, or whose, these clauses provide extra information.
- The building, which was built in 1920, still stands strong.
Why It Matters
Correctly enclosing nonessential modifiers ensures your writing is clear and grammatically accurate. It helps the reader understand what information is extra and what is essential. Misplacing punctuation or failing to identify nonessential elements can lead to confusion or misinterpretation.
For example
My friend Sarah who lives in London is coming to visit.(This suggests you have more than one friend named Sarah.)
My friend Sarah, who lives in London, is coming to visit.(This suggests you have one friend named Sarah, and she lives in London.)
Nonessential modifiers are enclosed in punctuation marks to signal that the added information is not required for the main meaning of the sentence. The most common punctuation used is commas, though parentheses and em dashes are also used for varying emphasis. Knowing how to identify and properly punctuate nonessential modifiers helps improve writing clarity and ensures that readers understand exactly what information is additional versus essential. By mastering the use of nonessential modifiers, writers can elevate their grammar and better control the rhythm and meaning of their sentences.