Presente Perfecto

El presente perfecto
El presente perfecto se usa en el idioma inglés para narrar hechos que ya han concluido pero en un tiempo breve, como hace dos horas o en menos de un día. El verbo en presente perfecto, o present perfect en inglés, se construye con el verbo auxiliar have o has, si es en tercera persona, he, she, it, más el participio del verbo, past participle, también conocido como 3ªcolomn (tercera columna)
Brevemente: sujeto + have/has + past participle.
* Ejemplos:
Afirmativo
He comido una manzana. → I have eaten an apple
Me ha comprado un coche. → He has bought me a car
Negativo
sujeto + haven't/ hasn´t + past participle.
No me ha llevado al zoo. → He hasn´t given me a lift to the zoo
Ellos no han estudiado para el examen. → They haven´t studied for the examPregunta
Have/has+ sujeto+ past participle?
¿Cuantas veces has visto esa película? → How much times have you seen that film?
¿Cuál ha sido la mejor película que has visto? → Which has been the best film have you ever seen?
Present perfect con for y since
"For" y "since" sirven para delimitar el tiempo de la acción del verbo. "For" significa durante y "since", desde.
* Ejemplos:
Afirmativo:He vivido aquí durante 4 años. → I have lived here for four years
He vivido aquí desde 2004. → I have lived here since 2004
Negativo:
No he estudiado durante seis años. → I haven´t studied for six years
No he estudiado desde 2002. → I haven´t studied since 2002
Present perfect con already, yet y just
Mientras for y since establecen cuando se ha concluido la acción mientras que already,just y yet.
* Already: ya
* Just: acabar de
* Yet: aún
Ya he hecho mis deberes. →I have already done my homework
Acabo de hacer mis deberes. → I have just done my homework
Todavía no he hecho mis deberes. → I haven't done my homework yet
Present perfect con ever
Ever significa siempre y se usa para expresar lo más interesante, lo más divertido que siempre he leído, visto oído...Se usa frecuentemente en preguntas. También sirve para preguntar sobre alguna "experiencia".
* Ejemplo:
¿Cual ha sido el libro más interesante que jamas has leído? → What has been the most interesting book you have never read?

Ejercicios
1. I am speaking to you. I have ___________to you.

2. That man is driving a car. That man has____________a car.

3. My friend is sleeping. Myfriend has_____________.

4. She is in Prague. She has ________________in Prague.

5. They are arguing about money. They have ____________money.

First Conditional: real possibility
We are talking about the future. We are thinking about a particular condition or situation in the future, and the result of this condition. There is a real possibility that this condition will happen. Forexample, it is morning. You are at home. You plan to play tennis this afternoon. But there are some clouds in the sky. Imagine that it rains. What will you do?
IF | condition | result |
  | present simple | WILL + base verb |
If | it rains | I will stay at home. |
Notice that we are thinking about a future condition. It is not raining yet. But the sky is cloudy and you think that it couldrain. We use the present simple tense to talk about the possible future condition. We use WILL + base verb to talk about the possible future result. The important thing about the first conditional is that there is a real possibility that the condition will happen. Here are some more examples (do you remember the two basic structures: [IF condition result] and [result IF condition]?):
IF | condition| Result |
  | present simple | WILL + base verb |
If | I see Mary | I will tell her. |
If | Tara is free tomorrow | he will invite her. |
If | they do not pass their exam | their teacher will be sad. |
If | it rains tomorrow | will you stay at home? |
If | it rains tomorrow | what will you do? |
 
result | IF | Condition |
WILL + base verb |   | present simple |
I will tell...