You may have learned the rules about using the indefinite article adjectives “a” and “an,” but when it comes to putting these rules into practice, you may end up second-guessing yourself. For example, if you’ve looked up this article, you’re probably trying to figure out, “Is it ‘a option’ or ‘an option’?” Fortunately, the answer is pretty straightforward.
An option is correct because the word “option” begins with a vowel sound. In this case, the vowel makes a vowel sound. Thus, it follows the standard rule of “a” before a consonant and “an” before a vowel. In some rare cases, words that begin with vowels are preceded by “a” (when they make consonant sounds), but this is not one of them.
We can often hear whether “a” or “an” should come before a word, but the correct choice may not always seem to follow the rules. For instance, while “an option” is correct, it also sounds correct to say “a one” rather than “an one,” even though they begin with the same letter. While this may seem confusing, there is a very concrete reason for these seeming exceptions.
When To Use “A” vs. “An” in General
You probably know the most basic rule for using the articles “a” vs. “an”: use “an” before a vowel (a, e, i, o, u, and sometimes y), and use “a” before a consonant (the rest of the letters). However, it isn’t always quite that straightforward.
Like most grammar rules, this one describes a phenomenon that arose naturally rather than a decision that someone made at some point about how the language would work.
For this reason, the rule actually has to do with whether or not the word that follows the indefinite article begins with a vowel sound or a consonant sound. Yes — sometimes vowels can make consonant sounds, and, rarely, a consonant can make a vowel sound.
First of all, let’s look at how these rules apply to using the indefinite article before the word “option.”
Which Article Is Used With Option?
We can either use the indefinite article “an” or the definite article “the” with “option.” The former depends on the vowel sound, while the latter does not depend on the word’s spelling.
Using the Indefinite Article “With Option”
The letters that we call consonants and vowels we categorize based on how we usually pronounce them in words. In the vast majority of cases, you can choose your indefinite article based on whether the letter that begins the next word is a vowel or a consonant.
This is the case with “option”: The letter “o” is a vowel, and it makes a vowel sound in this word — we begin with our mouths open when saying the word.
Thus, it is correct to say “an option.” Here are a couple of example sentences. Try reading them both aloud, and you will likely notice that the article “an” sounds more natural to your ear.
- Incorrect: Going back home was not a option.
- Correct: Going back home was not an option.
This is true with all of the various forms of the noun “option.” For example, the indefinite article “an” will always come before the adjective “optional” as well. Consider the following examples:
- Incorrect: There is a optional meeting after school.
- Correct: There is an optional meeting after school.
The indefinite article “an” is always correct when it comes before a vowel sound — a sound we make with our mouth open and without obstructing the flow of air in any way. Because “option” begins with a vowel sound, it will always follow the article “an,” no matter what form it takes.
The Definite Article “The”
In addition to the indefinite article “an,” we can use the definite article “the” with “option.” We use the definite article “the” before something someone has identified or specified. If we refer to “the option,” we expect the person we are speaking to understands what option we’re referencing.
- Those sunglasses were the best option.
- The options for sunglasses seemed endless.
In contrast, the indefinite articles refer to something in general or that we have not identified.
When an Adjective Precedes “Option”
Remember that the right indefinite article has to do with the sound that follows it. For instance, if we precede the word “option” with another word, you will select the indefinite article based on the sound that the word begins with and forget about the word “option” (source).
Consider the following sentences:
- He said that the green paint color was a option.
- He said that the green paint color was an option.
As we’ve discussed, the second example here is the correct one. But what if we add in an adjective modifying “option”?
- He said that the green paint color was a good option.
- He said that the green paint color was an good option.
Which of those sounds correct? Of course, it is the first one. Because the adjective “good” begins with the consonant “g” — you can feel the obstruction of the air in the back of your throat when you pronounce this word — it follows the indefinite article “a.”
When selecting an indefinite article, always remember that the only thing that matters is the sound you’ll pronounce directly after it, no matter what other words or sounds the rest of the sentence contains.
What Is the Difference Between a Vowel and a Consonant Sound?
What makes something a vowel or a consonant? The categories of “vowel” and “consonant” are merely descriptions of the natural ways that language works and how we form the words we pronounce.
We label letters as vowels or consonants based on how we shape our mouths when we articulate them. Basically:
- We form a vowel with our mouths open.
- We form a consonant with our mouths closed.
Try to say the word “apple” and then the word “pumpkin” and notice the difference — in the first word, your mouth starts open; in the second, it starts closed.
Some consonant sounds don’t begin with your lips completely closed in the way that the “p” sound does, but every consonant sound interrupts the flow of air through your mouth somehow. Here are some of the ways that we form consonants:
- Closing your lips (as for a “p” sound)
- Pressing your teeth against your lower lip (as for an “f” or “v” sound)
- Using your tongue to obstruct the air (as for an “l” sound)
It is easier to articulate a vowel sound after a consonant sound and easier to articulate a consonant sound after a vowel sound.
For this reason, language naturally developed such that “an” (which ends with the consonant “n”) precedes an open or vowel sound, and “a” (which is an open vowel sound) precedes a consonant sound in all cases.
You understand this naturally from hearing and speaking English, so whichever article sounds “right” to you very likely is. But now you know the reason why.
When Vowels Sound Like Consonants
Sometimes vowels and consonants behave in unusual ways in particular words, affecting the indefinite article that precedes them. Consider the sentence:
- Not a one of us liked the movie.
Notice that, while it begins with the same letter as “option” (the vowel “o”), the word “one” sounds more natural when we precede it with the indefinite article “a.”
Read the following sentence aloud and see if it sounds natural to your ear:
- Incorrect: Not an one of us liked the movie.
Why does “an option” sound correct when “an one” sounds incorrect? This has to do with how we form the words. While “o” is a vowel, notice that when you pronounce the word “one,” you begin with your lips pursed, forming a sound like a “w.”
Because we pronounce the beginning of this word by obstructing the flow of air through our mouths, as we would with a consonant, we use the indefinite article “a” instead of “an.” We cover this particular example more thoroughly in “‘A One’ or ‘An One’: Understanding Correct Grammar.”
Indefinite Articles With Vowel Sounds
We’ve covered the function of sound in determining which indefinite is correct for words beginning with “o.” Next, let’s explore more interesting examples of how indefinite articles operate when they precede vowel sounds.
Indefinite Articles with Vowels that Sound like Vowels
The most straightforward and common examples of this are when a vowel sounds like a vowel, like with the word “option.”
Here are some other examples of the indefinite article preceding words that begin with vowels that make vowel sounds. Read both the correct and incorrect examples and see how they sound to your ear. You should be able to tell which is correct intuitively.
- Incorrect: He bit into a apple.
- Correct: He bit into an apple.
The above is a good example of why the English language has developed to place the indefinite article “an” before vowel sounds. Notice that it is more difficult to say “a apple” than to say “an apple,” especially if you speak the sentence quickly.
- Incorrect: I like to wear a orange sweater in the fall.
- Correct: I like to wear an orange sweater in the fall.
Like “option,” the word “orange” starts with a vowel that makes a vowel sound. For this reason, the indefinite article “an” is correct here.
Indefinite Articles With Consonants That Sound Like Vowels
Remember that the indefinite article “an” comes before all vowel sounds, even when the vowel sound comes at the beginning of a word that starts with a consonant. Consider the following sentence:
- She said it was an honor to be invited to the dinner.
We categorize the letter “h” as a consonant, so we might expect the indefinite article “a” would precede it. However, read the following sentence aloud and see how it sounds:
- Incorrect: She said it was a honor to be invited to the dinner.
Why does this sound incorrect? In this particular case, the “h” is silent, so that when we pronounce the word, the initial sound is the vowel “o.” So, even though “honor” begins with the consonant “h,” the article “an” correctly precedes it (source).
While it is rare for words that begin with consonants to start with vowel sounds, there are some other examples. Consider the following:
- Incorrect: My brother is a honest man.
Does that sentence sound right to you? Probably not. Even though the word “honest” begins with the consonant “h,” we pronounce it with an open vowel sound. For this reason, the correct sentence is:
- My brother is an honest man.
If you are having trouble figuring out whether to use “a” or “an” before a word, think first of all about whether or not the word begins with a vowel or a consonant.
If something seems off, think about whether the word is an exception to the vowel/consonant pronunciation categories. Is it a vowel that sounds like a consonant in this case, or a consonant that sounds like a vowel?
Another instance is when placing the indefinite article before certain acronyms, in which we pronounce the first letter with a vowel sound (source). This article was written for strategiesforparents.com.
- Incorrect: Ralph drove a SUV through the mountains.
Even though the acronym “SUV” begins with the consonant “S,” when we pronounce the word, we begin by pronouncing the letter “S,” which sounds like “ess.” Because this begins with an open vowel sound, we instead use the article “an”:
- Correct: Ralph drove an SUV through the mountains.
In this article, we’ve covered the correct usage of the indefinite article “an” with the noun “option.” We’ve discussed the rules surrounding proper indefinite article use before vowel and consonant sounds, noting that we choose the indefinite article based on the beginning sound of the word it precedes.
Now you are equipped to tackle any question of which indefinite article to choose before any given noun. Remember that your ear is the best tool when it comes to this. If you are still struggling, go back to these rules, and you’ll be sure about which indefinite article to pick in no time.