FORM : has/have + past participle of the verb
- for something that started in the past and continues in the present:
They’ve known each other for nearly twelve years.
He has lived in Madrid all his life.
- for something we have done several times in the past and continue to do:
I’ve studied English ever since I was a eight.
He has traveled to different countries and he is traveling again soon.
We often use a clause with since to show when something started in the past:
I have worked here since I left school.
- when we are talking about our experience up to the present:
Note: We often use the adverb ever to talk about experience up to the present:
My last trip was the worst vacation I have ever had.
Note: and we use never for the negative form:
Have you ever met Alice?
Yes, but I’ve never met her husband.
- for something that happened in the past but is important at the time of speaking:
I can’t get in the house. I’ve lost my keys.
Peter isn’t at home. I think he has gone shopping.
- We use the present perfect of be when someone has gone to a place and returned:
A: Where have you been?
B: I’ve just been out to the store.
A: Have you ever been to New York?
B: No, but I’ve been to Las Vegas.
- But when someone has not returned we use have/has gone:
A: Where is Martha? I haven’t seen her for weeks.
B: She’s gone to Spain for a week. She’ll be back tomorrow.
- We often use the present perfect with time adverbials which refer to the recent past:
just; only just; recently;
Scientists have recently discovered a cure for this type of illness.
My cousins have just gotten back from our trip.
- or adverbials which include the present:
ever (in questions); so far; until now; up to now; yet (in questions and negatives)
Have you ever eaten Indian food?
Where have you been up to now?
Have you finished your project yet?
No, so far I’ve only done half of it.