Present perfect simple

the present perfect simple its formed by the present simple of the verb to have + the past participle of the principal verb. Remember: the past participle of the regular verbs its like the past.

Afirmative:
I/you 've watched tv (have)
He/she/it 's watched tv (has)
we/you/they 've watched tv (have)


Negative:
I/you haven't wathed tv (have not)
He/she/it hasn't watched tv (has not)
we/you/they haven't watched tv (have not)


Interrogative:
Have I watched tv?
Has you/he/she/it watched tv?
Have we/you/they watched tv?



Short answer:
Yes, I have/No, " haven't
Yes, you have/No, " haven't
Yes, he/she/it has/No, " hasn't
Yes, we/you/they have/No, " haven't


Use:
To talk about actions in the past that are important in the present:


Actions ocurred in the past without explanation of the moment.
ex:
I have met your mother in the supermarket


The adverb just express recently actions:
ex:
We have just come back from London


With the prepositions for and since
ex:
She has been abroad sonce 1999
I haven't eat pizza for two weeks


With expresions of time taht indicate a incomplete period: today, this morning, this week, this month, this year...
ex:
I haven't done much today





Present perfect continuous
Its formed with the present perfect of the verb to be + the principal verb finished in -ing



Afirmative:
I/you have been jumping
He/she/it has been jumping
We/you/they have been jumping



Negative:
I/ you haven't been jumping
He/she/it hasn't been jumping
We/you/they haven't been jumping


Interrogative:
Have I/you been jumping?
Has he/she/it been jumping?
Have we/you/they been jumping?


Use:
We use the present perfect continuous to:


To talk about an activity started in the past and continues in the present. Normally it uses the prepositions: for and since.
ex:
We have beenn cooking since 9 o'clock


To talk about a started action recently finished.
ex:
You have been sleeping all morning.


To talk about past actions recently finished with evident results.
ex:
Have you been hunting frogs?