Articles - The Indefinite Article

‘A’ or ‘an’ is termed as the indefinite article because it does not specify the noun it talks about. In other words, it leaves the noun indefinite.

For example:

A girl is singing. (Here, the noun ‘girl’ is left indefinite because of the use of the indefinite article. It is not specified as to which girl is singing.) An umbrella is missing. (Here, the noun ‘umbrella’ is left indefinite because of the use of the indefinite article. It is not specified as to which umbrella is missing.) A student should be regular about his studies. (Here, ‘student’ means all students in general. In this case, ‘a student’ represents the entire category of students.) I am looking for an honest person to do this job. (Here, ‘honest person’ means all honest persons in general. In this case, ‘an honest person’ represents any one honest person from the entire category of honest persons.) A Ms. Bindu is on the phone. (Here, ‘a’ is used before ‘Ms. Bindu’ so as to show that the person is not known to the speaker.)

The indefinite article is used for indicating a singular countable noun. In the previous examples, the indefinite article before each noun shows that exactly one girl is singing and that exactly one umbrella is missing.

The indefinite article ‘an’ is used when the word that follows it begins with a vowel sound.

For example:

He threw an egg at the player. (Here, ‘an’ is used because the word that follows—‘egg’— begins with a vowel sound.) The mail arrived an hour ago. (Here, ‘an’ is used because the word that follows—‘hour’—begins with a vowel sound.) He is an intelligent man. (Here, ‘an’ is used because the word that follows—‘intelligent’—begins with a vowel sound.)

The indefinite article ‘a’ is used when the word that follows it begins with a consonant sound.

For example:

There is a mouse in the room. (Here, ‘a’ is used because the word that follows—‘mouse’—begins with a consonant sound.) His father has a university degree. (Here, ‘a’ is used because the word that follows—‘university’—begins with a consonant sound.) I saw a beautiful umbrella. (Here, ‘a’ is used because the word that follows—‘beautiful’—begins with a consonant sound.)