English Grammer - Article A, An and The - Common usage example

Look at the following sentences taken from your lesson:

1. A man can’t know as much as a teacher.
2. Tommy finds a book.
3. Can I read the book with you after school?
In sentence 1, ‘A’ man / ‘a’ teacher refers to the tribe (whole class).

This is a generic reference.
In sentence 2, ‘a’ book refers to a particular, but not (yet) specified thing.
This is a specific reference (known but not specified)
In sentence 3, ‘the’ refers to a particular book.
This is a specific reference (known and specified)

Uses of the indefinite articles:
1. ‘A’ and ‘an’ are used with singular countable nouns.
e.g. The Inspector had a box of tools.
The Inspector gave Margie an apple.
2. ‘A’ and ‘an ‘ are used when talking about a person or
thing for the first time.
e.g. ‘I found a book.’.......... ‘Where did you find the
book?’

(When you refer to the same person or thing the second time, you use’the’.)
3. ‘A’ and ‘an’ are used with an adjective and a noun to give
more information about someone or something.
e.g. Tommy had found a real book!
The Inspector had a red face.
4. ‘A’ and ‘an’ are used to refer to ‘one’.
e.g. It was the old school of a hundred years ago.
5. A’ and ‘an’ are used in the sense of’any’.
e.g. A man can’t know as much as a teacher.

Common uses of the definite article:
‘The’ is used -
- in front of a noun
e.g The fun they had.
All the kids learnt the same things.
- when the person spoken to knows which person or thing
one means
e.g. Can I read the book with you after school?
- when one is referring to someone or something already
specified.
e.g. Margie had a mechanical teacher....... The teacher
gave her test after test.
- when one is referring to something unique
e.g. the sun, the moon, the earth
- before musical instruments
e.g. the guitar, the violin
- before mountain ranges, seas, rivers, gulfs, etc.
e.g. the Alps, the Red Sea, the Yamuna, the Gulf of
Mexico
- before superlatives
e.g. the best, the tallest
- before adjectives to talk about a general group of people
e.g. the rich and the poor
- before certain books
e.g. the Bible, the Vedas
- before ordinals
e.g. the 21st century
- as an adverb before comparatives
e.g. the more the merrier