Present Perfect Tense

FORMULA   :

(+) subject       +          auxiliary verb  +          main verb

                                   ( Have/Has)                (past participle)

(-)  subject       +          auxiliary verb  +          not       +          main verb

                                    ( Have/Has)                                     (past participle)

(?) auxiliary verb         +          subject             +          main verb ?

                                            ( Have/Has)                  (past participle)

EXAMPLE    :

 

	Subject	Auxiliary verb		Main verb
+	I	have		seen	ET.
+	You	have		eaten	mine.
-	She	has	not	been	to Rome.
-	We	have	not	played	football.
?	Have	you		finished?
?	Have	they		done	it?

 

FUNCTION  :

An aspect of the verb expressing an action that began in the past and which has recently been completed or continues into the present. Also known as the present perfective.

The present perfect is formed by combining has or have with a past participle (usually a verb ending in -d, -ed, or -n).

The present perfect tense is used to describe action that began in the past and continues into the present or has just been completed at the moment of utterance. The present perfect is often used to suggest that a past action still has an effect upon something happening in the present.
            Each of the highlighted compound verbs in the following sentences is in the present perfect tense.

1.      They have not delivered the documents we need.

-          This sentence suggest that the documents were not delivered in the past and that they are still undelivered.

2.      The health department has decided that all high school students should be immunized against meningitis.

-          The writer of this sentence uses the present perfect in order to suggest that the decision made in the past is still of importance in the present.

3.      The government has cut university budgets; consequently, the dean has increased the size of most classes.

-          Here both actions took place sometime in the past and continue to influence the present

4.       The heat wave has lasted three weeks.

-          In this sentence, the writer uses the present perfect to indicate that a condition (the heat wave) began in past and continues to affect the present.

5.      Donna has dreamt about frogs sitting in trees every night this week.

-          Here the action of dreaming has begun in the past and continues into the present.