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The present perfect tense (simple and continuous)

1. Form

The present perfect simple is formed with the present tense of have + the past participle:

I have worked. I have not worked. Have you worked? Haven’t you work?

He has worked. He has not worked. Has he worked? Hasn’t he work?

The present perfect continuous is formed by the present perfect of the verb to be + the present participle:

I have been working I haven’t been working have you been working?

He has been working He hasn’t been working Has he been working?

This tense is a sort of mixture of present and past. It always implies a strong connection with the present and is chiefly used in conversations, letters, newspapers and television and radio reports.

2. The Present Perfect Used for Past Actions Whose Time is not Definite

A.The present perfect is used for recent actions when the time is not mentioned:

I have read the rules but I don’t understand them.

Have you seen my passport? - Yes, I have.

Yes, I saw it on your desk a minute ago.

B. Recent actions in the present perfect often have results in the present:

I’ve lost my key. (=I haven’t got it now.)

The lift has broken down. (=We have to use the stairs.)

C. It can also be used for actions which occur further back in the past, provided the connection with the present is still maintained, i.e. the action could be repeated in the present:

John Carter has written a number of short stories means that he is still alive and can write more.

But if John Carter is dead we would say:

John Carter wrote a number of short stories.

3. The Present Perfect Used for Actions Occurring in an Incomplete Period

A. An incomplete period may be indicated by today or this morning/afternoon/evening/week/month/year/century etc.

Note that the present perfect can be used with this morning only up to about one o’clock, with this afternoon up to about five o’clock and so on because after that time they become completed periods and actions occurring in them must be put into the simple past:

(at 11 a.m.) Tom has rung up three times this morning.

(at 2 p.m.) Tom rang up three times this morning.

(at 4 p.m.) I haven’t seen Tom this afternoon.

(at 6 p.m.) I didn’t see Tom this afternoon.

The present perfect used with an incomplete period of time implies that the action happened or didn’t happen at some undefined time during this period:

Have you met Ann today? (at any time today)

But if we know that an action usually happens at a certain time of our incomplete period we use the simple past tense. If my alarm clock normally rings at 7 o’clock, I might say at breakfast:

My alarm clock didn’t ring this morning.

B. lately, recently used with the present perfect also indicate an incomplete period of time and mean ‘at any time during the last week/month etc.’ Note that both lately and recently are used in negative and interrogative sentences but in affirmatives recently is generally used:

Has he been here lately/recently?

He hasn’t been here lately/recently.

but: He has been here recently.

C. The present perfect can be used similarly with ever, never, always, occasionally, often, several times:

-Have you ever fallen off a horse?

-Yes, I’ve fallen off quite often/occasionally.

D. The present perfect used with for and since:

1. for is used to say how long something has lasted.

for used with the present perfect denotes a period of time extending into

the present:

We have lived in London for ten years. (and still live there)

for used with the past simple denotes a terminated period of time:

We lived in London for ten years. (but we don’t live there now)

for can be omitted, especially after be, live and wait:

We’ve waited for you an hour.

for (denoting time) is not used before expressions beginning with all:

They’ve worked all night.

2. since is used if we say when something started in the following ways:

since + a point in time means ‘from that point to the time of speaking’:

She has been here since six o’clock.

We’ve been friends since 1975.

since + clause, in which the present perfect or the simple past can be used depending on the meaning:

I’ve known her since we were children. (we aren’t children any more)

I’ve known her since I’ve lived here. (and still live here)

since, or ever since, adverb:

We had a letter last week. We haven’t heard about him since.

He had an accident last year and has been off work ever since.