When do you use a Present Perfect?
* events which started in the past but the effect is still noticeable in the present
* experiences in the past (date is not important
Examples:
I can't run, I have broken my leg. (your leg is still broken today)
I have known my boyfriend for 5 days. (you still know him)
I have been to London six times. (Date is not important, you might go again)