The two indefinite articles are "A - An".
Indefinite means "not specific", so we use them when we are talking about something in general.
I need a pencil.
(any pencil, not a specific one).
ARTICLE
"A" + Consonant
We use "A" or "An" depending on the first letter of the word following the article.
We use "A" when the following word starts with a consonant or u/eu when it sound like "You".
Examples
A cat.
British
American
A hero.
British
American
A university.
British
American
A flower.
A european girl.
ARTICLE
"An" + Vowel
We use "An" when the following word starts with a vowel or a mute "H".
Examples
An elephant.
British
American
An honor.
British
American
An orange.
An hour.
ARTICLE
"A/an" + New Info
We use "A - An" to refer to something for the first time, when we introduce something new to a listener.
Examples
I bought a new car.
I'm talking about the car for the first time.
Kate is a doctor.
This is new information about Kate.
ARTICLE
"A/an" + Singular Nouns
We use "A - An" to talk about singular nouns, since they mean "One" or "A unit".
Examples
I'd like a cup of tea and some biscuits.
I'd like one cup of tea and some biscuits.
That is an elephant.
That is one elephant.
ARTICLE
"A/an" No Genre
The use of "A - An" does not depend on the gender of the nouns, we use them both for female and male nouns.
Examples
A boy.
A girl.
A bike.
A car.
An elephant.
An umbrella.
An orange.
In English, the only definite (specific) article is "The".
We use "The" to talk about something that has already been mentioned or that the listener already knows, for example...
I have a car. The car is blue.
Remember the girl we were talking about yesterday?
We use "The" to talk about things that are unique or known by everybody, for example...
The sun.
British
American
The Atlantic ocean.
When "the" is followed by a Vowel sound, we say... /ðiː/
British
American
The moon.
The president of the USA.
The world.
We use "The" to talk about both singular and plural nouns, for example...
The flower.
The flowers.
The car.
The cars.
1 I think you are _____ hero.
2 Jenny has travelled around _____ world.
3 We use the article "The" to talk only about plural nouns.
4 Do you know Jason? He's _____ great footballer.
5 Where is _____ blue umbrella?
6 Both "A" and "An" are Indefinite Articles.
7 The article "An" is used when the following word begins with a vowel.
8 We use the Indefinite Articles "A - An" to talk about…
9 That is _____ car I have been talking about.
10 I need _____ pencil! Anyone!
11 I'd like _____ pie and a cup of tea, please.
12 Did you see _____ elephant during your trip to Africa?
13 I wait you here in _____ hour.
14 How beautiful is _____ Moon!
15 I have a shirt. _____ shirt is yellow.