How do we make the Present Perfect Tense?

The structure of the Present Perfect is:

subject + auxiliary have + main verb
conjugated in Present Simple  
have, has past participle

The auxiliary verb (have) is conjugated in the Present Simple: have, has

The main verb is invariable in past participle form: -ed (or irregular)

For negative sentences we insert not between the auxiliary verb and the main verb.

For question sentences, we exchange the subject and the auxiliary verb.

Look at these example sentences with 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?

Contraction with Present Perfect

When we use the Present Perfect in speaking, we often contract the subject and auxiliary verb. We also sometimes do this in informal writing.

I have I've
You have You've
He has
She has
It has
John has
The car has
The car's
We have We've
They have They've

In negative sentences, we may contract the auxiliary verb and "not":

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 Simple tense, passive voice)
It is usually clear from the context.