A and an are what are called indefinite articles. Indefinite articles give us information about nouns. A and an tell us that there is only one of the nouns. For example: a book, or an apple. But how do you know which to pick? How do you know if you should use a or an? Are there exceptions to the rules? If you’ve always been curious, read on to find out!

Indefinite Article: A

You use the article a before singular countable nouns. It is also used before nouns that begin with a consonant (not a vowel – a,e,i,o,u) sound.

For example:

  • a cat
  • a book
  • a show
  • a TV program
  • a cousin

Nouns that start with a consonant use a. There are also some nouns, however, that begin with a vowel, but where a is used as an exception. This is because the noun starts with the consonant-like sound- you. That means that they are treated like a noun that starts with a consonant.

For example:

  • a university (“you”-niversity)
  • a unique situation (“you”-nique)
  • a united country (“you”-nited)

Another exception is if the word starts with a hard h sound.

For example:

  • a history class
  • a hospital
  • a helpful hand

Different English accents can have an effect on how a or an is used. British English speakers tend to use an in front of words that begin with h. This is because they pronounce the words that start with h harder and more emphasized.

For example:

  • UK English: a herb garden (the h is strongly pronounced)
  • US English: an (h)erb garden – the h is silent

Indefinite Article: An

Just like a, an is used before singular countable nouns. However, an is used before nouns that start with a vowel sound.

For example:

  • an actor
  • an example
  • an invitation
  • an umbrella

Some words start with a consonant, but are used with an instead of a. This is because some consonants are soft, like some h sounds, or because the consonant has a vowel sound at the beginning.

For example:

  • an hour (silent/soft h)
  • an F (efff)
  • an MBA degree (em-BA)

It’s important to know that it’s not always the spelling that counts with a and an, but the sound! If you don’t know which one to use, say the word in your head or out loud. This will help you pick whether to use a or an.

Do you need any help with a and an? Let us know if you have a question in the comments below!

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Erin Duffin lives in Hamburg, is an English teacher, blogger, yoga instructor, and has a unique ability to select a great blog topic every week! She has a history of tremendous feedback and a huge following! 

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