Present Perfect :

We use :

• For actions that happened in teh past, but we don´t say when exactly.

Eg:
I have visited Cuba.

• With the time expressions: ever, never,before, so far, yet, already, always for, since, etc.

Eg:
She has been in Canada for 3 years.

Affirmative Form:

Subject + Has/ have +  verb participle + complement

Eg: She has been a teacher for 14 years.

Negative Form:

Subject + hasn´t/ haven´t + verb participle + complement

Eg: He ha´sn´t come to my house yet.

Question Form:

Has/ have + Subject  + verb participle + complement ?

Eg: Has She worked in KFC?

Bueno ese esel tema de Presente Perfecto. Saludos