Form: Subject + has/have + Form 3 (past participle) of the verb
I have spoken to my friend.
I have not spoken to my friend.
Have you spoken to your friend?
I can use it to talk about something that happened at an * indefinite time in the past, and has a significance in the present. I can also use it along with expressions like ‘already’ and ‘yet’, as well as in conjunction with ‘for’ and ‘since’. My focus is more on the experience rather than the event itself.
Suma has come to Dubai. She came in 2009. (*When there is a mention of a definite time, I use the Past Simple, rather than the Present Perfect.)
I have not visited Thailand yet.
Preetha has already made plans for her summer vacation.
I have worked in a language institute for a year.
Sally has been a teacher since 2001.