Use of present tense

How do we use the Present Perfect Tense?
This tense is called the present perfect tense. There is always a connection with the past and with thepresent. There are basically three uses for the present perfect tense:
1. experience
2. change
3. continuing situation
1. Present perfect tense for experience
We often use the present perfect tense to talk about experience from thepast. We are not interested in when you did something. We only want to know if you did it:
|I have seen ET. |
|He has lived in Bangkok. |
|Have you been there?|
|We have never eaten caviar. |
|past |present |future ||[pic] |
|!!! |
||
| |
|The action or state was in the past. |In my head, I have a memory now. |  |


Connection with past: the event was in the past.
Connection with present: in myhead, now, I have a memory of the event; I know something about the event; I have experience of it.







2. Present perfect tense for change
We also use the present perfect tense to talk about a change or new information:
|I have bought a car. |
|past|present |future |
|- |+ |  |
|Last week I didn't have a car. |Now I have a car. | |


 
|John has broken his leg. |
|past |present |future |
|+ |- | |
|Yesterday John had a good leg. |Now he has a bad leg. |  |


 
|Has the price gone up? |
|past |present|future |
|+ |- |  |
|Was the price $1.50 yesterday? |Is the price $1.70 today? |  |


 
|The police have arrested the killer....