The indefinite article – a, an

1. The indefinite article – a

The indefinite article a is the same for all genders.

  • a boy
  • a girl
  • a cat

The indefinite article has no plural form.

  • a boy → boys

We use an if the following word starts with a spoken vowel.

the following word starts with a spoken consonant the following word starts with a spoken vowel
  • a boy
  • a school
  • a girl
  • an aunt
  • an old school
  • an American girl
Mind the pronunciation of the following word.
The first sound we speak is [j], so we use aa unit The first sound we speak is [ʌ], so we use anan uncle

2. Use of the indefinite article a/an

2.1. before phrases of time and measurements (per week/weekly)

  • We have English 4 times a week.
  • I go on holiday twice a year.
  • Our car can do 220 kilometres an hour.
  • Tomatoes are $2 a kilo.

2.2. before phrases of jobs

  • My father is a car mechanic.

2.3. with a noun complement

  • He is a good boy.

2.4. before phrases of nationality

  • Bruce Springsteen is an American.

2.5. half/quite

  • We need half a pound of sugar.
  • This is quite a good story.