English grammar help: when to use ‘a’ or ‘an’

Finding the difference between using ‘a’ and ‘an’ is something my students really struggle with. My younger students especially stress themselves out trying to decide whether it’s “a apple” or “an apple”, and whether it’s “a umbrella” or “an umbrella”. So here are some great ways of remembering which one to use.

There is one simple way of remembering this. When the word begins with a vowel sound (a,e,i,o,u) then you should use ‘an’ as it sounds better and feels easier to say.

When the word begins with a consonant you should use ‘a’. If you use words and phrases such as ‘ball’, ‘glass of water’ or ‘cup of coffee’, then it would be “a ball”, “a glass of water” and “a cup of coffee”.

However with this rule there is one exception. If you are using a word with a silent ‘h’ such as ‘honourable’ or ‘honest’ then you have to use ‘an’. Therefore it would be “an honourable man” and “an honest mistake”.

With words such as ‘umbrella’, ‘ice cream’ and ‘apple’ you have to use “an umbrella”, “an ice cream” and “an apple”.

Unfortunately there are some exceptions to this rule too. When ‘u’ makes the same sound as the ‘y’ in “you”, or ‘o’ makes the same sound as ‘w’ in “won” then you should use ‘a’. An example of this would be “a one-legged man” and “a European trip”.

As long as you follow these methods of remembering it should be easy to know when to use ‘a’ or ‘an’.