Present Perfect

Used in connection with a specified time that continues from the past until now.

I’ve done a lot of work today.
(I’m still doing work.)
He has lived in London for eight years.
(He’s still living there.)
It hasn’t rained for a week.
(It’s still not raining.)
She’s been with us since 1995.
(She is still with us.)
I have never missed a deadline.
(This is true for the past and the present.)
Have you seen the CFO recently?
(Asking about the recent past and the present.)
When have they ever broken an agreement?
(Asking about the past and the present.

Signal words: for, still, since, never, recently, ever

Used to talk about things that started in the past and continue or can continue to the present.

We’ve travelled extensively.
(We are still travelling on a regular basis.)
John Grisham has written numerous novels.
(The author is still alive and writing novels.)

Used to make a statement about the present while talking about a past event.*

Tim has finished his project.
(The project is finished now.)
Has anyone opened the window?
(It is cold in the room now.)
I’ve found the technical documentation.
(I have it now.)
Fred has left the company.
(He is no longer an employee.)

* Important note: In American English, the present perfect and the simple past can both be used in this case.