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Articles: A versus An

Summary:

This short handout deals with which article to use before a noun -- "a" or "an."

Contributors:Chris Berry, Allen Brizee
Last Edited: 2011-07-27 11:20:13

How do you know when to use the indefinite articles?

The choice of article is actually based upon the phonetic (sound) quality of the first letter in a word, not on the orthographic (written) representation of the letter. If the first letter makes a vowel-type sound, you use "an"; if the first letter would make a consonant-type sound, you use "a." However, you may follow these basic rules when deciding to use "a" or "an," remembering that there are some exceptions to the rules.

"A" goes before words that begin with consonants.

"An" goes before words that begin with vowels:

Exceptions

Use "an" before unsounded "h." Because the "h" hasn't any phonetic representation and has no audible sound, the sound that follows the article is a vowel; consequently, "an" is used.

When "u" makes the same sound as the "y" in "you," or "o" makes the same sound as "w" in "won," then a is used. The word-initial "y" sound ("unicorn") is actually a glide [j] phonetically, which has consonantal properties; consequently, it is treated as a consonant, requiring "a."

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