A. Talking about actions that continue at the time of speaking
She is driving to work.
They are working on the farm
Kate is doing homework, don’t disturb her
Where is Alex – he is having a bath ( NOTE: ‘have‘ has many different meanings)
Let’s go out now it isn’t raining (Not, rain is not coming)
She is tired, she is going to bed.
Let’s go out now. It isn’t raining any more. (not ‘it doesn’t rain’)
Hello, Albert are you having fun? (at a party)
B. Sometimes the action may not be happening at the time of speaking
She is reading a novel (from the past week)
John is learning German at a local school.
Elisabeth is working hard, yes she has a lot to study
C. To describe changes happening around us
The prices of cars are going up
The Global temperature is increasing at an alarming rate
Sarah’s French is getting better.
D. To describe Planned action
I am meeting the Principal tomorrow morning
The president is visiting the city tonight.
Grammar
I + am
we/you/they + are
He/Sh/It + is
Who (singular) + is
Who (plural) + are