Notice:
As rule, unless a singular countable noun has already got a determiner, we must use either a, an or the in front of it.
The is used in the following cases:
In front of all nouns except proper nouns or when we are referring to something for the second time and thereafter.
"E.g. I met a cat; the cat was eating the rat.
When or if the listener knows exactly what the speaker is talking about. E.g. Sit on the bench; shut the door.
The is used before ordinal numbers like first, second, third, tenth E.g.: The man is the first in the race; I was the second
The is used to refer to thing or group of things commonly or universally known. The moon the star, the west ...
When singular things are turned into plural ones, changes into some
E.g:
- I have a book (singular)
* I have some books (plural)
