Sarah is in her car. She is on her way to work. She is driving to work.
This means: she is driving now, at the time of speaking. This action is not finished.

I am doing something = I'm in middle of doing something; I've started doing something and I haven't finished.
Sometimes action is not happening at the time of speaking!
'I am reading a really good book at the moment. It's about a man...'
with today/this week/this year
'You're working hard today.'
changes happening around now, especially with verb:
get change become increase rise fall grow improve begin start

	Criado por Aleksandra Juszczakiewicz aproximadamente 7 anos atrás

Notes for unit 1