Unit 7. Present perfect (1) (I have done)

The present perfect simple is have/has + past participle. The past participle often end in -ed (finished/decided etc.), but many importantverbs are irregular (lost/done/been/written etc).

When we use the present perfect there is always a connection with now. The action in the past has a result now.

• Where's your key? / I don't know. I've lost it. ( I haven't got it now )
• He told me name but I've forgotten it. ( I can't remember it now )

We often use the present perfect to give new information or to announce a recent happening.

• Ow! I've cut my finger.
• The road is closed. There's been (= there has been) an accident.

You can use the present perfect with just, already and yet :

Just = a short time ago
  - Hello. Have you just arrived?
  - Would you like something to eat? / No, thanks. I've just had lunch.

We use already to say that something happened sooner than expected.
  - Don't forget to post the letter, will you? / I've already posted it.
  - What time is Mark leaving? / He's already gone.

Yet : 'until now' and shows that the speaker is expecting something to happen. 
       Use yet only in questions and negative sentences.
  - Has it stopped raining yet?
  - I've written the letter but I haven't posted it yet.

Note the difference between gone (to) and been (to):

• Jim is away on holiday. He has gone to Spain. (= he is there now or on his way there)
• Jane is back home from holiday now. She has been to Italy. (= she has now come back from Italy)