Present Perfect Tense
I have sung
The present perfect tense is a rather important tense in English, but it gives speakers of some languages a difficult time. That is because it uses concepts or ideas that do not exist in those languages. In fact, the structure of the present perfect tense is very simple. The problems come with the use of the tense. In addition, there are some differences in usage between British and American English.
In this lesson we look at the structure and use of the present perfect, followed by a quiz to check your understanding:
• Structure: how to make the present perfect tense  • Use: when and why to use the present perfect tense  • For and Since with the present perfect tense. What's the difference?  • Present Perfect Quiz 
The present perfect tense is really a very interesting tense, and a very useful one. Try not to translate the present perfect tense into your language. Just try to accept the concepts of this tense and learn to "think" present perfect! You will soon learn to like the present perfect tense!  How do we make the Present Perfect Tense?
The structure of the present perfect tense is:
subject + auxiliary verb + main verb   have  past participle
Here are some examples of the present perfect tense:
  subject auxiliary verb   main verb   + I have   seen ET. + You have   eaten mine. - She has not been to Rome. - We have not played football. ? Have you   finished?   ? Have they   done it?
Contractions with the present perfect tense
When we use the present perfect tense in speaking, we usually contract the subject and auxiliary verb. We also sometimes do this when we write.
I have I've
You have You've
He has She has It has John has The car has
He's She's It's John's The car's
We have We've
They have They've
Here are some examples:
• I've finished my work.  • John's seen ET.  • They've gone home.  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 the present. 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 the past. We are not interested in when you did something. We only want to know if you did it:
I have seen ET.
He's or he's??? Be careful! The 's contraction is used for the auxiliary verbs have and be. For example, "It's eaten" can mean: 
• It has eaten. [present perfect tense, active voice]  • It is eaten. [present tense, passive voice] 
It is usually clear from the context. 
He has lived in Bangkok. Have you been there? We have never eaten caviar.
past present future !!!   
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 my head, now, I have a memory of the event; I know something about the event; I have experience of it.