Guide to English grammar

've had these skis for years.
I had those skis for years. (Then I sold them.)
I've been here since three o'clock.
I was there from three o'clock to about five. (Then I left.)
Compare the past simple for an action.
I bought these skis years ago.
I arrived here at three o'clock.

3 When we use the present perfect for repeated actions, it means that the action may happen again. The past simple means that the series of actions is over.

Gayle has acted in more than fifty films. (Her career has continued up to now.)
Gayle acted in more than fifty films. (She is dead, or her career is over.)

Look at this news report.

There has been a serious accident on the M6. It happened at ten o'clock this morning near Preston when a lorry went out of control and collided with a car...
The present perfect is used to give the fact of the accident and the past simple for details such as when and how it happened. We often use the present perfect to first mention a topic and the past simple for the details.
I've just been on a skiing holiday. - Oh, where did you go?
Have you sent in your application? - Yes, I sent it in ages ago.

5 Adverbials of time with the present perfect and past simple

Some adverbials used with both forms are “just, recently, already, once/twice etc, ever/never, today, this morning/week etc” and phrases with “for” and “since”.

For American usage, • 303(6).

1 With just and recently there is little difference in meaning.
I've just heard the news./I just heard the news.
We've recently moved house./We recently moved house.
Compare these examples with already.
I've already heard the news. (before now)
I already knew before you told me. (before then)

2 Once, twice etc with the present perfect means the number of times the action has happened up to now.

We've been to Scotland once/lots of times.
This is the third time my car has broken down this month.
With the simple past once usually means “at a time in the past”.
We went to Scotland once.
Ever/never with the present perfect means “in all the time up to now”. With the simple past it refers to a finished period.