A

Is used in front of singular contable nouns which are no specific.

We don`t use before uncontable or plural nouns.

If a noun starts with consonants sound.

EXAMPLES: A cat - A bird - A house.

AN

An is used in front of singular contable nouns which are not specific.k

We don`t use an before uncontable or plural nouns.

If the noun starts with a vowel sound comes before the noun.

EXAMPLES: An apple - An egg - An orange.

THE

We use the in front of nouns to describe someone or something specific or unique

EXAMPLES: The eart - The world - The air.