Present continuous tense

PRESENT CONTINUOUS TENSE:

1.   The use:
    ● a/ to express an action that is going on at the time of speaking.

 I am writing a letter.
She is studying.
           ● b/ As substitute for the immediate future.
She is leaving this place tomorrow.
My father is coming back this Friday.
           ● c/ Used with today, this week, this year, tonight, now , right now, at the moment...
He is working hard today.
The company I work for isn't doing so well this year.

1.  Difference between present simple & Present continuous tense.
   ● simple present is used for things in general or things that happen regularly.

 I surf the net every evening.
I always go to school.

          ● simple present is used for permanent situations.
He lives in New York.
    
           ● Present continuous is used for things happening at or around time of speaking. 
I am getting hungry let's go and eat.

            ● Present continuous is used for temporary situations . 
I am staying at my cousin's house this day, until I find a place of my own.