Present Perfect
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FORM Present Perfect
[HAS / HAVE] + [past participle]
EXAMPLES:
I have seen that movie many times.
I have never seen that movie.
NOTE: When you are using a verb tense with more than one part such as Present Perfect (have seen), adverbs usually come between the first part and the second part (have never seen).
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USE 1 Unspecified Time Before Now
We use the Present Perfect to say that an action happened at an unspecified time before now. The exact time is not important. You CANNOT use the Present Perfect with time expressions such as "yesterday," "one year ago," "last week," "when I was a chlid," "when I lived in Japan," "at that moment," "that day" or "one day." We CAN use the Present Perfect with expressions like "ever," "never," "once," "many times," "several times," "before," "so far," "already" and "yet."
EXAMPLES:
I have seen that movie twenty times.
I think I have met him once before.
There have been many earthquakes in California.
Has there ever been a war in the United States?
Yes, there has been a war in the United States.
People have traveled to the moon.
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IMPORTANT How do you actually use the Present Perfect?
The concept of "unspecified time" can be very confusing to English learners. It is best to associate Present Perfect with the following topics:
TOPIC 1 Experience
You can use the Present Perfect to describe your experience. It is like saying, "I have the experience of..." You can also use this tense to say that you have never had a certain experience. The Present Perfect is NOT used to describe a specific event.
EXAMPLES:
I have been to France.
(This sentence means that you have the experience of being to France. Maybe you have been once, or several times.)
I have been to France three times.
(You can add the number of times at the end of the sentence.)
I have never been to France.
(This sentence means that you have not had the experience of going to France.)
I think I have seen that movie before.
He has never traveled by train.
Joan has studied two foreign languages.
Have you ever met him?
No, I have not met him.
TOPIC 2 Change Over Time
We often use the Present Perfect to talk about change that has happened over a period of time.
EXAMPLES:
You have grown since the last time I saw you.
The government has become more interested in arts education.
Japanese has become one of the most popular courses at the university since the Asian studies program was established.
My English has really improved since I moved to Australia.
TOPIC 3 Accomplishments
We often use the Present Perfect to list the accomplishments of individuals and humanity. You cannot mention a specific time.
EXAMPLES:
Man has walked on the moon.
Our son has learned how to read.
Doctors have cured many deadly diseases.
Scientists have split the atom.
TOPIC 4 An Uncompleted Action You Are Expecting
We often use the Present Perfect to say that an action which we expected has not happened. Using the Present Perfect suggests that we are still waiting for the action.
EXAMPLES:
James has not finished his homework yet.
Susan hasn't mastered Japanese, but she can communicate.
Bill has still not arrived.
The rain hasn't stopped.
TOPIC 5 Multiple Actions at Different Times
We also use the Present Perfect to talk about several different actions which occured in the past at different times. Present Perfect suggests the process is not complete and more actions are possible.
EXAMPLES:
The army has attacked that city five times.
I have had four quizes and five tests so far this semester.
We have had many major problems while working on this project.
She has talked to several specialists about her problem, but nobody knows why she is sick.
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IMPORTANT
When we use the Present Perfect it means that something happened at some point in our lives before now. Remember, the exact time the action happened is not important.
Sometimes we want to limit the time we are looking in for an experience. Expressions such as "in the last week," "in the last year," "this week," "this month," "so far" and "up to now" can be used to narrow the time we are looking in for an experience.
EXAMPLES:
Have you been to Mexico in the last year.
I have seen that movie six times in the last month.
They have had three tests in the last week.
She graduated from university less than three years ago. She has worked for three different companies so far.
This week my car has broken down three times.
NOTICE
"Last year" and "in the last year" are very different in meaning. "Last year" means the year before now. "In the last year" means from 365 days ago until now.
EXAMPLES:
I went to Mexico last year.
(I went to Mexico in 1998.)
I have been to Mexico in the last year.
(I have been to Mexico at least once at some point between 365 days ago and now. We do not know exactly when.)
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USE 2 Duration From Past Until Now (Non-continuous Verbs)
With Non-continuous Verbs and some non-continuous uses of Mixed Verbs, we use the Present Perfect to show that something started in the past and has continued up until now. "For five minutes," "for two weeks" and "since Tuesday" are all durations which can be used with the Present Perfect.
EXAMPLES:
I have had a cold for two weeks.
She has been in England for six months.
Mary has loved chocolate since she was a little girl.
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ACTIVE / PASSIVE Present Perfect
EXAMPLES:
Many tourists have visited that castle. ACTIVE
That castle has been visited by many tourists. PASSIVE
الرئيسية 
