He perfect tense is a verbal tense of our language that allows us to refer to an action carried out in the past . There are two types of perfect past: the simple past and the past perfect compound .
He simple past it is used when the act in question is located in a moment before expression . In these cases, the activity is considered already finished and does not have a necessary link with the I presented .
For example: “The day before yesterday I had lunch with Rodrigo in a downtown restaurant”. As you can see, the speaker points to a action that took place in the past ("the day before yesterday"), using the simple past tense for conjugation of the verb ("I lunched"). That lunch does not continue, but concluded.
Others examples Simple past: "The policeman shot without hesitation", "The old man wrote his will in a few minutes and handed it to the lawyer", “I already got out of the shower”.
He past perfect compound , meanwhile, places the action at an instant prior to the present, but in a period that it's not over yet . The activity , in this framework, it maintains a relationship with the current period of time.
With the past perfect compound, in short, it is indicated that there is still a influence of the action taken. The construction of these expressions is done with the auxiliary verb to have more him participle of the verb .
"I've yelled a lot in the game" It is an example of the past perfect compound. The subject comments that some time ago he forced his voice ("I have shouted"), which could be suggesting the possible cause of a dysphonia.