PRESENT PERFECT

The present perfect is a verb tense which is used to show that an action has taken place once or many times before now. The present perfect is most frequently used to talk about experiences or changes that have taken place, but there are other less common uses as well.

STRUCTURE

• POSITIVE:

(+) SUBJECT + AUXILIAR HAVE/HAS  + VERB (PAST PARTICIPLE) + COMPLEMENT.

• NEGATIVE:

(-) SUBJECT + AUXILIAR HAVE/HAS + NOT + VERB (PAST PARTICIPLE) + COMPLEMENT.

• INTERROGATIVE:

(?) AUXILIAR HAVE/HAS + SUBJECT + VERB (PAST PARTICIPLE) + COMPLEMENT?

AUXILIAR HAVE/HAS CONJUGATION

I - HAVE

YOU - HAVE

HE - HAS 

SHE - HAS

IT - HAS

WE - HAVE

YOU - HAVE

THEY - HAVE

EXAMPLES

(+) I have studied for the English class.

(-) I have not studied for the English class.

(?) Have I studied for the English class?

(+) He has bought a new guitar.

(-) He has not bought a new guitar.

(?) Has he bought a new guitar?