A, an, and the are adjectives, but they have another name: articles.
Remember: adjectives in a sentence include a, an, and the.
Use a or an when you are not definite about a particular person or thing.
A and an are called indefinite articles.
examples:
A man means any man.
An apple means any apple.
Use a before a consonant:
a school
a mirror
a glove
Use an before a vowel:
an apple
an envelope
an icicle
If a word is pronounced as if it begins with a vowel, use an before it, even though the word really starts with a consonant.
an hour
an honest man
Use the if you refer to some particular person or thing.
The is called a definite article.
Compare the meaning of a and the in these sentences.
A flower in the vase would be pretty.
The flower in the vase is fragrant.
In the first sentence any flower is meant.
In the second sentence, one particular flower is indicated.
Good luck with your writing. jt