When to Use the Indefinite Article "a"?

 Know the Rules in Using the IndefiniteArticle "a."

1. Use "a" before an adjective that starts with a consonant sound describing a singular non-specific countable noun.

For example: a big girl

a - article

big - adjective (starting with the consonant sound b)

girl - singular (not specific) countable noun

More examples: 

a small table

a long bench

a beautiful girl

2.   Use "a" before a singular non-specific countable noun that starts with a consonant sound.

For example: a computer

a - article

computer - singular (not specific) countable noun (starting with a consonant sound (k) for computer.

More examples: 

a ring

a kitchen

a door

a man

3. Use "a" if it's the first time you introduce the idea to the person you are talking to.

For example:  I saw a girl at a party.

a - article

girl - (first time to mention that idea to another person)

More examples:

I saw a colorful bird in our garden.

I met a lovely woman.

I talked to a stranger today.

Note: To be able to able to know if you will use "a" or not before your noun, you have to know first if the noun is countable or uncountable: List of Countable and Uncountable Nouns