A, An, and The - three are called articles.

In grammar, an article is a determiner used before a noun to indicate the definiteness or indefiniteness of the noun.

 There are two types of articles in grammar:-

1. Definite articles (the)
2. ​Indefinite articles (a/an)
   

For example:--

• ​ He is a blind man.

1. I have an umbrella.
2. The sky is blue.

Indefinite Article    
What is an Indefinite article?

A and An both are called Indefinite articles.

- The indefinite article” a” or “an ” is used to refer to a non-specific noun.

- And also it is used to describe a singular noun for the first time.

- The choice between “a” and “an” depends on the sound that starts the next word.

- “A” or “AN” is placed before a singular noun to refer to a non-specific person, thing, or place.

Some examples of indefinite articles:- 

1. A dog is barking.
2. He eats an apple.
3. He writes a letter.
4. Mukta reads a book.
5.  He lives in a hotel.
   

• “A dog is barking.” In this sentence “A” is an indefinite article. Because their “dog“refers to a non-specific person. That's why “A” is placed before a singular noun.

  -  There are some kinds (a non-specific person) of examples:-

1. ​He is an honorable man.
2. He is an honest man.
3. He is a happy man.
4. He is a lame man.
5. He is a one-eyed/one-legged man.
   

• ​“He writes a letter.” in this sentence “A” is an indefinite article. Because their “letter” refers to a non-specific thing that's why “A” is placed before a singular noun.
  - There are some kinds( a non-specific thing) of examples:-

1. ​She writes a letter.
2. Mukta reads a book.
3. I have a pen.
4. One takes note.
5. This is a useful thing.

• ​“He lives in a hotel.” in this sentence “a”- is an indefinite article. Because their “hotel” refers to a non-specific place. That's why “a”- is placed before a singular noun.
  

There are some kinds(a non-specific place) of examples:-

1. This is a university.
2. They have a house/ home.
3. In our college, we have a library.
4. I want to visit a museum tomorrow.
5. She was taken to a hospital.
   

•  More Indefinite Article with roles and examples - Indefinite Article

Definite Article (The)

What is a definite article?

- “The“- is called a definite article.

- The definite article “the” refers to a specific noun.

- And also implies that the reader is already familiar with the nouns being referred to.

-“The”- is placed before both singular and plural nouns to indicate a specific person, thing, or place.

Some examples of definite articles:-

1. The sun rises in the east.
2. The English know English.
3. He has gone to the United Kingdom(UK)
4. Mother reads the Quran every day.
5. The Taj looks very beautiful.

• More Definite Article with roles and examples - Definite Article

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