Why is the definite article "the" used so frequently in English?

Because the definite article can be used before singular, plural forms and uncountable nouns to express a "specific" meaning. Nouns appear more frequently in English sentences.

The is used in the following situations:

1. Before the noun of something unique in the world.

The sun, the moon, the earth, etc.

2. Used before nouns of people or things that both parties know.

Close the door, please.

3. Before the noun of the person or thing mentioned for the second time.

I read a story. The story is

interesting.

4. Used before nouns of direction or location.

Shanghai is in the east of China.

5. Used before ordinal numbers and superlatives of adjectives.

John is the tallest boy in our

class.

6. Used before the names of mountains, rivers, seas, lakes and islands.

the Yellow River

7. Used before common nouns to form proper nouns.

the United Nations

8. Used before nominal adjectives to express a type of person or thing.

the young

9. Used before the noun of the musical instrument played.

play the piano, play the violin

10. Used before the plural form of a surname to indicate a family.

the Smiths

11. Used in fixed phrases

by the hour, make the most of

etc. .

Hope this helps!