The present tenses in English

The present tenses in English: 

Forms of the present:
English uses two forms of the present, the present simple and the Present Progressive.
The present simple 
In short, the Present Simple is used to express:
   a) permanent states and permanent truths.
   b) repetitive actions
   c) instant actions.
Examples:
   a1) I like apples, but I don't like oranges.
   a2) I live in London, and I work for a big bank.
   a3) Flowers grow well in a warm sunny climate.
   a4) Tomorrow never comes
   b1) My brother often goes to London.
   b2) It snows in winter in New York.
   b3) I get up at 6 every morning.
   c1) Oh, I understand what you mean.
   c2) And now Owen gets the ball, he shoots, and he scores!
The present progressive 
In short, the Present Progressive is used to express:
   a) developing  situations.
   b) actions that are actually taking place.
   c) future actions.
Examples:
   a1) John is getting better.
   a2) The weather is improving.
   b1) This week I am working in New York.
   b2) Look! That man's stealing my car!
   b3) Careful! You're driving too fast!
   c1) He's going on holiday tomorrow.
   c2) He said he's retiring next year.
Note: some verbs are almost never used in the present progressive - notably certain verbs of permanent state, such as know, be, like, exist.
   We can say: I know the train is arriving late.
   We cannot say: I am knowing the train is arriving late.
A contrastive example :
This sentence is a clear example of the difference in usage between the two forms:
  I eat hamburgers, but I'm not eating a hamburger right now.