In English we have three times - the past, the present and the future. However, sometimes we want to use two different times in the same sentence.
When we want to connect two different times with the same idea, we use the perfect tense. When we want to connect the past with the present, we use the present perfect.
Grammatically the perfect tense has two parts. The main part is the 'third part' of a verb, which is properly called the past participle. For example, the parts of the verb 'sing' are 'sing, sang, sung'. 'Sung' is the past participle. The main part of the verb gives its meaning, but we only know it is in the perfect tense if we see the auxiliary 'have' in front of it. If we look at the time of the auxiliary 'have' we can see if we are looking at a past, present or future perfect.
'Had sung' is in the past perfect tense
'Have sung' is in the present perfect tense
'Will have sung' is in the future perfect tense
The present perfect and the past
The present perfect does not exist in many languages, and it is therefore difficult for many students to understand how it is used in English. However, it is a really useful tense, so it is worth taking the time to understand it properly.
Basically, the present perfect tells you that something happened in the past and it is still true.
You are reading this on your computer. Therefore, in the past before you started to read this, your computer was turned on. It is still turned on. So the person who turned on the computer can say 'I have turned on the computer' and because this person has used the present perfect, you know that the computer is still on. When the computer is turned off again, he uses the past tense. 'I turned on the computer'.
For another example, think of a pet dog (Let's call him 'Spot')
It is much better to be able to say
'My dog, Spot, has lived for five years.'
'My dog, Spot, lived for five years.'
because in the second sentence, poor Spot has stopped living.
Past events, present importance
Because the present perfect connects the past and the present, we use it not just for things that happened in the past and are still true, but also for things that happened in the past and are important now. So, for example, if you are discussing France, you might ask someone 'Have you been to France?'. Even though the visit to France might have happened years ago, it is relevant to the present discussion, so we can use a present perfect to connect the past visit with the present conversation.
Interviewer: Do you have any qualifications?
Interviewee: Yes, I have passed all the exams.
Joe: There's a problem
Jane: What have you done?
Present perfect and time indicators
Because the present perfect is a present tense, you cannot use it with any time indicator except words that mean 'now', such as 'today' or 'this month/year'.
We cannot say I have eaten a good dinner yesterday.
But we can say I have eaten a good dinner today.
This year the weather has been excellent.
Last year the weather was terrible.
You can, however, use time indicators to show how long something has been happening until now.
Fred has just arrived. (Fred arrived very recently and is still here)
Fred has not arrived yet. (Fred has not arrived up until now, but we are hoping he will)
Fred has been here for three hours. (Fred arrived three hours ago, and is still here)
Present perfect continuous
This is used when we want to describe something that happened in the recent past, and even though it has stopped, the results are still immediately obvious. We can also use 'to be' in the present perfect with an adjective to do this.
Joe: Why are you so short of breath?
Jane: I have been running.
Joe: You look pleased to see me.
Jane: I've been lonely.
Have you understood? Now you have read all about the present perfect, let's do some exercises!
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