Present Perfect

Form

The present perfect of any verb is composed of two elements : the appropriate form of the auxiliary verb to have (present tense), plus the past participle of the main verb. The past participle of a regular verb is base+ed, e.g. played, arrived, looked. For irregular verbs, see the Table of irregular verbs in the article called 'Irregular Verbs'.

Affirmative
Subject	to have	past participle
She	has	visited
Negative
Subject	to have + not	past participle
She	hasn't	visited
Interrogative
to have	subject	past participle
Has	she	visited..?
Interrogative negative
to have + not	subject	past participle
Hasn't	she	visited...?

Example: to walk

Affirmative	Negative	Interrogative
I have walked	I haven't walked	Have I walked?
You have walked	You haven't walked	Have you walked?
He, she, it has walked	He, she, it hasn't walked	Has he,she,it walked
We have walked	We haven't walked	Have we walked?
You have walked	You haven't walked	Have you walked?
They have walked	They haven't walked	Have they walked?

Function

The Present Perfect is used to indicate a link between the present and the past. The time of the action is before now but not specified, and we are often more interested in the result than in the action itself.

BE CAREFUL! There may be a verb tense in your language with a similar form, but the meaning is probably NOT the same.

The Present Perfect is used to describe:

1. An action or situation that started in the past and continues in the present. Example: I have lived in Bristol since 1984 (= and I still do.)
2. An action performed during a period that has not yet finished. Example: She has been to the cinema twice this week (= and the week isn't over yet.)
3. A repeated action in an unspecified period between the past and now. Example: We have visited Portugal several times.
4. An action that was completed in the very recent past, (expressed by 'just'). Example: I have just finished my work.
5. An action when the time is not important. Example: He has read 'War and Peace'. (the result of his reading is important)

Note: When we want to give or ask details about when, where, who, we use the simple past. Example: He read 'War and Peace' last week.

Examples:

1. Actions started in the past and continuing in the present.

• They haven't lived here for years.
• She has worked in the bank for five years.
• We have had the same car for ten years.
• Have you played the piano since you were a child?

2. When the time period referred to has not finished.

• I have worked hard this week.
• It has rained a lot this year.
• We haven't seen her today.

3. Actions repeated in an unspecified period between the past and now.

• They have seen that film six times.
• It has happened several times already.
• She has visited them frequently.
• We have eaten at that restaurant many times.

4. Actions completed in the very recent past (+just).

• Have you just finished work?
• I have just eaten.
• We have just seen her.
• Has he just left?

5. When the precise time of the action is not important or not known.

• Someone has eaten my soup!
• Have you seen 'Gone with the Wind'?
• She's studied Japanese, Russian and English.

Present perfect + ever,never,already,yet

The adverbs ever and never express the idea of an unidentified time before now e.g. Have you ever visited Berlin?

'Ever' is used

·         in questions. e.g.
Have you ever been to England?
Has she ever met the Prime Minister?

·         in negative questions e.g.
Haven't they ever been to Europe?
Haven't you ever eaten Chinese food?

• and in negative statements using the pattern nothing.......ever, nobody.......ever e.g.
  Nobody has ever said that to me before.
  Nothing like this has ever happened to us.
• 'Ever' is also used with 'The first time.... e.g.
  It's the first time (that) I've ever eaten snails.
  This is the first time I've ever been to England.

'Never' means at no time before now, and is the same as not ..... ever:

• I have never visited Berlin

BE CAREFUL!
You must not use never and not together:

• I haven't never been to Italy.
• I have never been to Italy.

Position

'Ever' and 'never' are always placed before the main verb (past participle).

Already and yet

Already

refers to an action that has happened at an unspecified time before now. It suggests that there is no need for repetition, e.g.
a. I've already drunk three coffees this morning. (and you're offering me another one!)
b. Don't write to John, I've already done it.

It is also used in questions:

• Have you already written to John?
• Has she finished her homework already?

Position

already can be placed before the main verb (past participle) or at the end of the sentence:

• I have already been to Tokyo.
• I have been to Tokyo already.

Yet

is used in negative statements and questions, to mean (not) in the period of time between before now and now, (not) up to and including the present. e.g.

• Have you met Judy yet?
• I haven't visited the Tate Gallery yet.
• Has he arrived yet?
• They haven't eaten yet.

Position

Yet is usually placed at the end of the sentence.

Present Perfect + for and since

Using the present perfect, we can define a period of time before now by considering its duration, with for + a period of time, or by considering its starting point, with since + a point in time.

For + a period of time

• for six years, for a week, for a month, for hours, for two hours.
• I have worked here for five years.

Since + a point in time

• since this morning, since last week, since yesterday,
• since I was a child, since Wednesday, since 2 o'clock.
• I have worked here since 1990.

Present perfect with for

• She has lived here for twenty years.
• We have taught at this school for a long time.
• Alice has been married for three months.
• They have been at the hotel for a week.

Present perfect with since

• She has lived here since 1980.
• We have taught at this school since 1965
• Alice has been married since March 2nd.
• They have been at the hotel since last Tuesday.

Note:

• For and since can both be used with the past perfect.
• Since can only be used with perfect tenses, for can also be used with the simple past.

Present Perfect of Simple Past?

How to choose between the Present Perfect and Simple Past Tenses

• Always use the Present Perfect when the time is not important, or not specified.
• Always use the Simple Past when details about the time or place are specified or asked for.

Compare:

Present Perfect	Simple Past
I have lived in Lyon.	I lived in Lyon in 1989.
They have eaten Thai food.	They ate Thai food last night.
Have you seen 'Othello'?.	Where did you see 'Othello'?
We have been to Ireland.	When did you go to Ireland?

There is also a difference of attitude that is often more important than the time factor.

• "What did you do at school today?" is a question about activities, and considers the school day as finished.
• "What have you done at school today?" is a question about results - "show me", and regards the time of speaking as a continuation of the school day.

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