Present Perfect Tense

In this lesson Rama Explains how we form and use the Present Perfect tense, Godzilla attacks and snakes are eaten.

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First we look at how we form the Present Perfect tense. We form the Present Perfect tense by using have/has +the past participle ( sometimes called verb 3) There is no easy trick to remembering all the forms of the past participle. You just have to try to remember all the forms and using them in conversation will help you remember. The verb have/has is the helper verb and the present participle is the main verb. The helper verb have/has is used to help make the Present Perfect but does not really have any meaning on its own in the Present Perfect. Have/has in the Present Perfect is very different from have/has in the Present Simple. In the Present Simple have/has has meaning. In the sentence ‘I have a dog named Rex.’,’ have’ is the main verb and has a lot of meaning. It shows that the dog is yours. But in the Present Perfect sentence ‘I have eaten snake.”, ‘have’ doesn’t really have much meaning, ‘eaten’ has the meaning ‘has’ just helps make the sentence the Present Perfect.
To form questions with the Present Perfect we take the helper verb have/has and move it to the front of the sentence. So ‘You have packed your bag.’ Becomes ‘Have you packed your bag?’ To make the Present Perfect negative just put a ‘not’ behind the helper verb ‘have’. So our example sentence becomes “You have not (or haven’t) packed your bag.”
Next, is the big one. How and why we use the present perfect tense. We use the Present Perfect tense when we want to say how long the present moment is and then talk about something that happened in that present moment. When we use the Present Perfect we talk about a moment of time that must include NOW and call that whole amount of time, that whole ‘chunk’ of time, the present moment. Sometimes we specify the time like ‘this week’ or ‘this year’ (see how both those ‘chunks’ of time include now) but sometimes it is just implied like in the sentence “My wife has made pancakes.” The amount of time is ‘this morning’ in the sentence. Or, “Have you ever been to Rome?” the amount of time is your whole life.
The amount of time cannot include the past. You cannot talk about any point in time or any moment or ‘chunk’ of time that does not include now. If you talk about the past you must use the Past Simple. For example you can say “I have seen the new Star Wars movie.” In this case the present moment is the time from when the movie first opened in the Theatre up until the present moment. But you cannot say “I have seen the new Star Wars movie last week.” In this sentence you point to the past and give an amount of time that does not include NOW so you must use the past simple, you should say “ I saw the new Star Wars movie last week.
This explanation of how and why we use the Present Perfect is very helpful to explain a tricky tense that is the Present Perfect.
‘Already’ and’ yet’ are often used with the Present Perfect. ‘Already’ emphasizes that something has been completed and ‘yet’ says that we expect that an action will be completed.
‘For’ and ‘since’ are often used with the Present Perfect. ‘For’ is used just before an amount of time, the amount of time to be used in the Present Perfect. ‘Since’ is used just before a moment in time that is the start of the moment that is used in the Present Perfect.