FORMATION. The Present Perfect tense is formed with the help of the auxiliary have/has and the Past Participle of the main verb.

The Present Perfect tense is formed with the help of the auxiliary have/has and the Past Participle of the main verb.

Table 6

Affirmative	Negative	Interrogative
I you	have	worked     come	you	have not	worked     come	have	I you	worked?     come?
he she it	has	he she it	has not	has	he she it
we you they	have	we you they	have not	have	we you they

Contractions:

've = have

's = has

haven't = have not hasn't = has not

USAGE

The Present Perfect tense denotes:

1. Completed past actions connected in their result with the present either because of the actual evidence of the result or its importance for the present. The recent comp­letion of an action is often expressed by the adverbials 'recently, lately, already' 'in affirmative sentences and the adverbial 'yet 'in questions and negatives.

I've recently (lately) spoken to him on the phone. I'm afraid I've forgotten my key. Do you want some more coffee? - No, thanks, I've already had enough.

Has your younger brother left school yet? Slie hasn 't found the dog yet.

To show that something has happened very recently the adverbial just is used.

Mary has just gone out.

Just now, however, which means 'a moment ago' is used with the Past Simple.

Mary went out just now.

There can be no adverbial in the sentence when the present evidence of the result of a completed past action is clear from the context.

My mother is angry because I've lost my watch.

The importance of a completed past action for the present stands out clearly in complex sentences with superlative constructions, ordinal numerals or 'the only'in the principal clause.

It's the best salad I have eaten in this restaurant.

It's the second time I have seen this film.

This is the only place he's been to.

This is the first time I've felt really relaxed.

The Present Perfect for completed past actions is often used with today, this morning, this week, this year, etc. when these periods are not over.

/ have written three letters this morning, (when it is still 'this morning')

It must be remembered that the Present Perfect is not used with 'definite past time' adverbials like yesterday, last time, a year ago, the other day, etc. These adverbials are used with the Past Simple which emphasizes the time of the event. Compare, e.g.:

Deborah has ironed your shirt, (emphasis on the

result)

Deborah ironed your shirt yesterday morning.

(emphasis on the time of the action)

2. Incomplete actions that started in the past, lasted over a period of time and are still taking place in the pre­sent. The Present Perfect in this meaning is typical of verbs not used in the continuous aspect but is not limited to them. The starting point of the action is expressed by an adverbial with 'since' while an adverbial with 'for' is used to denote a period of time. (Compare the use of similar adverbials with 'for' with the Past Simple). Such adverbs as ever, never, lately, recently, always, often, all my life, so far, etc. are also often used with the Present Perfect to denote incomplete past actions.

They have been married for 20 years.

I've lived here since 1992.

Have you ever ridden a helicopter?

I have never tasted papaya.

She 's been here several times before.

Compare the use of the Past Simple and the Present Perfect tense-forms.

1. Ann bought herself a new dress yesterday. She paid 30 pounds for it.

2. Have a look. I've just bought a lovely pair of shoes.

3. Marie and Pierre Curie discovered radium and in 1903 won the Nobel Prize.

4. The police haven't found the boy yet. He disappeared 3 days ago.

5. How many times have you been in love? When did you fall in love first?

6. Ron hasn't studied much this term.

7. When did they get married? - Last year. So they have been married for about a year.

8. Chemistry has never been my favourite subject. I liked Maths when I studied at school.

9. Sam hasn't drunk alcohol since he got into a car accident.

10. I bought everything I needed and went straight home.

11. I have bought a new car. - But where's the car you bought last year?

12. That's where I used to live in my childhood.

13. Where is your key? - / don't know. I'm afraid I've lost it. - But when did you see it last?

14. Peter was meeting someone that night so I stayed at the office and worked Jor a few extra hours.