How to use articles (1): a, an and the

In my first language, there are not any articles. So I am sometimes confused about them. According to articles used,  languages can be roughly classified into two categories: without articles like Chinese and Japanese, and with articles like English and Western European languages (however,they are slightly different in the way articles used).

However, we mainly discuss articles in English. Why we need to use articles? This is because they can show whether we are talking about things that are known both to the speaker and the listener (definite: the), or that are not known to them both(indefinite: a/an). Usually there are two basic rules:

  • To say 'you know which I mean', then put the before a noun.
            I've been to the agent.(you know which one: my agent)
            Could you pass the pen?(you can see the pen that I want)

  • When we cannot say 'You know which I mean', we:
         put a/an before a singular countable noun
            There is a bottle in the kitchen.
            I want
an apple.
         put no article with a plural or uncountable noun.
            He likes apples. I need help.

We also need to notice that:
         1. Don't use a/an with plural or uncountable nouns.
             Lily need water.(not a water)
         2. Don't use the to talk about things in general.
             Petrol is expensive.(not the petrol)
         3. Don't use articles together with my, this, or other determiners.
             my work(not the my work), a friend of mine(not a my friend)
         4. Don't use singular countable nouns alone, without an article or other determiner.Say a cat, my cat, this cat, any cat, but not just cat.