They are my best friends.

We have built a close relationship.

Their closeness is the result of years of collaboration.

The results of the exam are out.

Years of effort finally bore fruit.

He has been working as a doctor in this town for many years.

I haven't seen him for a long time.

He has been working as a doctor in this town for many years.

He was immersed in his work all day.

He was working all day.