Present Perfect
The present perfect in English we used to talk about past actions that have some connection with this. For instance:
-She has found a dog. - (Ella) Ha encontrado un perro.
-We have known each other for years - Nos conocemos desde hace años.
Another example is when what happened in the past has a direct effect on our current situation.
How do you use it
When we talk about an action that took place in the past, but did not specify when it happened, we use the present perfect. We can say that, by not specifying the time, we are placing the action in the course of our lives, that is, at some point since we were born until now.
Here is the connection with this use of the present perfect.
-They have lived here since 1977 - Han vivido aqui desde el 1977 - Y siguen viviendo aqui.
-I have worked here for 3 years - He trabajado aqui durante 3 años - Y aun trabajo aqui.
I have lost my keys - I lost my keys - How did you come home now?
I have Studied a lot - I've studied a lot - I'll pass the exam today.
How it is formed
To form the perfect present we must use the correct form of this auxiliary verb 'to have', 'have' or 'has' (see the simple present), followed by the past participle of the verb desired.
Affirmation
Subject + have / has + verb (participle) + (add)
