When to use ’a’ versus ’an’

’A’ or ’an’? Well, normally the rules are clear, but there are exceptions if the word is pronounced differently than it looks.

If a word begins with a consonant sound, you must use ’a’. If it begins with a vowel sound, use ’an’. In other words, using ’a’ and ’an’ does not depend on the spelling of the word it comes before; it depends on the pronunciation of the word. For example:

• an honours student (starter med o-lyd)
• an MSc in Engineering (starter med e-lyd)

• a one-hour lunch break (w-lyd)
• a unit (starter med j-lyd)
• a university professor (starter med j-lyd)
• a European conference (starter med j-lyd)
• a US book publisher (starter med j-lyd)