Grammar Tips & Articles »

"A" and "AN" - How to use?

This article is about "A" and "AN" - How to use? — enjoy your reading!

3:14 min read
  Kanthasamy Ahilan  —  Grammar Tips
Font size:

Hi friends,

The general rule is that, “an” is to be used before a vowel and “a” is to be

Used before a consonant.

This rule is applicable in most of the situations.

But in some cases the word “an” is used before consonant and at the same time the word “a” is used before a vowel.

Because, the actual usage of "a" and "an" in English is not related to whether,

it has to come before a vowel or a consonant.

It is totally depends on the sound of the first letter, i.e., whether it is taking the sound of a vowel or a consonant.

lets see in detail;

1. Words begin with a vowel but not using "an" before it.

Case 1: Few of English vowels take two sounds. For example the English letter ‘u’ sometimes take the sound "ah" and sometimes "yoo".

Case 2: In case of the word one, the first letter is taking the sound of "wa" which is not a vowel sound. So "one" will not have the prefix "an" instead it will have "a". For example: "a one-day match".

Case 3: There are several English words for which the first letter will be silent. When that silent letter is a vowel then the word will take the sound of the second letter. And, if the second letter takes the sound of a consonant then it will have the prefix as "a" before it.

- For example: in the word Euro the first letter

"E" is silent, and it takes the second letter as the initial sound "yoo", which is not a vowel sound. So it is "a Euro" not

"an euro".



eucalyptus, euglena, eukaryote ,eulachon,

eulogy, eureka, euro, Euro-American, European bison, ewe, one, Ukrainian,

unary, uni, unicorn, uniform, union, unique, unit, unite, unity, univalent,

universal, universalism, Universalism, universe, university, univocal, Unix,

uranium, urinal, urinalysis, urine, uro, usability, usable, usage, use, user,

US-ian, using, usufruct, usufruction, usufructuary, utensil, uterus, utile,

utilitarian, utility, uvula, uvular, etc.

2. Words begin with consonant but use the word ‘an’ before it:

For this issue there are three situations:

=> In words:

1. When the first character of the word is consonant and is silent, then it takes the second character as the the initial sound and when such sound is initiated from a vowel then that word will be having the word “an” as the prefix.

    > For example: in the word hour the, the first character "h" is silent, and the sound is initiating from the vowel "o", so the word ‘hour’ will have “an” as the prefix.     

    - Illustration: (Half an hour, be there in an hour)

    - Examples: Heir, heiress, heirloom, honest, honesty, honor, honorable, hour, hourly, etc.


2. In abbreviations:
> whenever the consonants f, h, l, m, n, r, s and x comes as the first letter of an Abbreviation then that Abbreviation will have the word “an” before it. Because all these letters having "euh" as the initial sound when it is spelled separately.

o For Illustration:  “an FBI officer”, “an NGO”, ……….

o Examples: FBI, HRM, HTML, LML, MOU, NGO, RDA, SC,




Abbreviations used as a word:

o When you use an abbreviation as a word then

the above rule is not applicable.

o For example: NATO, NASA, etc.

Special Note:

The concept of the usage of “a” and “an” is little difficult to understand through English.

But, if you know any one of the Indian based language then it is very easy to understand this concept of vowels in English.

To make this easy, just write the word in any of the Indian language directly as pronounced.

Rate this article:

Have a discussion about this article with the community:



    Use the citation below to add this article to your bibliography:


    ""A" and "AN" - How to use?." STANDS4 LLC, 2024. Web. 24 Jul 2024. <>.

    Checkout our entire collection of

    Grammar Articles


    Free, no signup required:

    Add to Chrome

    Check your text and writing for style, spelling and grammar problems everywhere on the web!

    Free, no signup required:

    Add to Firefox

    Check your text and writing for style, spelling and grammar problems everywhere on the web!


    Free Writing Tool:

    Grammar Checker

    Improve your grammar, vocabulary, style, and writing — all for FREE!


    Are you a grammar master?

    Identify the sentence with correct use of the present continuous tense:
    A She is playing the piano at the moment.
    B They have played football every Sunday.
    C She had finished her work before the meeting started.
    D We will be leaving for the airport soon.

    Improve your writing now:

    Download Grammar eBooks

    It’s now more important than ever to develop a powerful writing style. After all, most communication takes place in reports, emails, and instant messages.