• 3-minute read
• 16th July 2015

Indefinite Articles: When to Use “An” Instead of “A”

The problem with the English language is that it rarely sticks to its own rules. This can be confusing when it comes to ensuring high grammatical standards.

The indefinite article, for example, can be either “a” or “an” depending on the situation. And while this is probably a word you use on a daily basis without even thinking about it, it is still one that many people find confusing.

Why Are There Two Versions of This Word?

There are two versions of the indefinite article in English because it is easier to pronounce “an” than “a” when it comes before a word beginning with a vowel. Using “an” separates the article from the following noun, so “an office” is correct but “a office” would sound wrong to most people.

The general rule is to use “an” before words beginning with vowels and “a” before words beginning in consonants. But, as with most rules, there are exceptions to this, which is where things get tricky.

Hard Vowels

One important exception is words beginning with hard vowels. This includes any word that starts with a vowel but sounds like it doesn’t, such as “university” or “Europe.”

Although these words start with “u” and “Eu” respectively, they are pronounced with a “you-” sound at the beginning. For instance, it is “you-niversity” rather than “oo-niversity.”

In cases like this the word should be preceded with “a” rather than “an,” as in the following example:

The koala lived in a eucalyptus tree – Correct

The koala lived in an eucalyptus tree – Incorrect

Soft Consonants

Another issue that many find confusing is whether to use “an” before words starting with “h.” This is, in fact, much simpler to resolve in American English than in other English speaking countries, where words like “historical” and “heroic” are sometimes pronounced with a silent “h.”

In Britain, for example, you might meet people who write “an hotel” rather than “a hotel.” But in the US this is very rare. If in doubt, the key again lies in the pronunciation. Do you pronounce the “h” at the start of the word? If so use “a”; if not use “an.” For example:

There was a house on a hill – Correct

There was an house on an hill – Incorrect

Basil is an herb commonly used in Italian cuisine – Correct

Basil is a herb commonly used in Italian cuisine – Incorrect

In summary, if you’re ever confused about whether to use “a” or “an” in your writing, try reading it out loud; if it starts with a consonant sound, use “a,” while words which start with a vowel sound need “an.”

And if ever you see a horned horse flying a rotary aircraft, remember that it’s “a unicorn piloting a helicopter” and not “an unicorn piloting an helicopter.”

You’ll find more helpful grammar tips on our academic blog, while if you’d like to have your work checked by one of our expert proofreaders here at Proofed we offer a variety of services to meet your specific requirements.