Indefinite Article

Education English | Indefinite Article | “A” is traditionally called the indefinite article. Its alternate form “an” is used before words beginning with vowel sounds – An apple, an obstruction, an ink bottle, an hour, an heir, an honest man ( words beginning with silent ). The indefinite article is just the opposite of the definite article. It is called “indefinite” because they do not refer to a particular thing as “the” does, but simply refer to an object or person in a non-specific way, that is, we do not specify exactly to which person or object we are refering to.
Frank (1972:135) states the uses of the indefinite article “a” as follows :
1. “A” meaning the numeral one
I wanted an hour.
He paid a hundred dollars to his suit
Closely related to the numerical use of a is the distributive use of “a” in the sense of each – His rent is $200 a month ; these apples cost $.25 a pound.
2. “A” signaling one specimen that represents a class
In this case, no attempt is made to distinguish one individual number of class from any other specimen in the same class. “A” occurs most often in a statement about one event.
He ate an apple.
A prize will be given to the best student.
This is the true indefinite use of “a”. Such indefinite use is far more common than any other use of a.
3. “A” with nouns ( usually considered noncountable)
“A” is used in a general statement to classify a noun. In this use, a points to any representative of a class – a lion (=any lion) is very strong. This is the generic
a that we have already looked at.
“A” often appears with a class word in the predicate after a form of the verb be.The class word after this verb may serve to :
a. Identify an individual
John is a student.
John is a good student who is not discourged by failures. ( class word with modifier)
b. Definite a smaller class
The lion is an animal.
The lion is a large, powerful mammal of the cat family, found in Africa and Southwest Asia, with a tawny coat, a tawny coat, a tufted tail, and in the adult male, a shaggy mane.
4. “A” with Nouns Usually Considered Noncountable.
Nouns that have both countable and noncountable forms are often derived from verbs, and end in such suffixes as –ment, -ion, -ance, -ary.The noncountable word refers the act itself – operation, mixture, shipment, goverment – and the countable word to the of the act – an imitation, a shipment, a goverment.
The child learns through imitation.
But Arts is an imitation of life.
This picture is a good imitation. 

Certain noncountable nouns that do not have a plural form may neverthless be used with a, especially if they have adjective modifiers.
He exhibited a courage that suprised me.
We encountered an unexpected friendliness wherever we went.
“A” may also occur with a noncountable noun that is in apposition with another noun used earlier. Often the appositive noun repeats the noun it refers to. 

He felt remorse over what he had done, a remorse that grew with the passing of time.
5. A after such, what
A is required after such or what used with a singular countable noun.
Such a pretty face
What pretty nouse
6. A after certain adverbs or adjectives – not a, many a, quite a, rather a.
There was quite a large crowd in the street.
Not a man volunteered. (=not one man volunteered)
Many a man has volunteered to flight for his country. (literary usage)
7. A before noun quantifiers – a few, a lot of, a little.
A few chairs
A little furniture
8. A with proper names, meaning a certain.
A Mr. Smith called you
9. A with most in the sense of very (often considered informal usage)
She is a most beautiful woman.
But She is the most beautiful women I know. (Most marks the superlative
degree)
10. A after so or too – an adjective+ a singular noun
She is too sensible a girl to do a thing like that.
She is so sensible a girl that she could not do a thing like that.
11. Half an hour or a half hour.
Either form may be used – she waited for half an hour (or a half hour).
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