0There are two types of Articles:-
1- Indefinite Article - A, An
2- Definite Article - The.
A is used for consonant sounds.
An is used for vowel sounds.
Example:-
A union is necessary to protect our fundamental rights.
An elephant is a big animal.
Use of The:-
The is used for specified things.
Example:-
1- The gold of Nepal is not pure.
2- I met a girl. The girl is my brother 's friend.
The is used before the names of rivers, mountain (not for mountain peak), gulf, bay, historical evens, governmental institutions, newspapers, books, trains etc.
