Articles A-AN

They will always accompany a noun, this noun will always be an accounting noun and will always be in its singular form.

Use "a" before all words that begin with a consonant sound.

-They have a car.
-The dog is playing with a ball.
-I am reading a book.

Use "an" before all the words that start with vowel sounds.

-You need an umbrella because it’s raining a lot.
-An ant was walking on my pillow.

We use a / an when we describe people or things.

-She is a doctor
-My girlfriend is a beautiful woman

We do not use the names or nouns that are written in plural or are countless, because a / an means "uno".

-My grandparents are teachers (not...a teachers)
-Would you like some bread? (not...a bread)

We do not use a / a with an ad that is alone and without a noun.

Carla is very good (Not Carla is a very good)

We do not use a / an together with another determinant, such as my and your.

She is a friend of mine (Not She is a my friend)