English Grammer - Present Perfect.

They HAVE GONE out. (= they are not at home NOW)

He HAS CLEANED his shoes. (= his shoes are clean now).

👉has cleaned / have gone etc. is the Present Perfect (has / have + past participle):

👉We use the present perfect for an action in the past with the result now.

• We have bought a new car. (we have a new car now)
• 'Where's Udit?'   'He has gone to bed.' (he is in bed now)
• It's Udit's brithday tomorrow and I have not bought him a present.
• I have lost my passport. (I can't find my passport now)
• 'Udit is on holiday.'   'Oh, where has he gone?'
• Can i take this newspaper? Have you finished with it?

 👉I have just... (JUST = a short time ago)

• A: Are Udit and Dipika here?
  B: Yes, they have just arrived.
• A: Are you hungry?
  B: No, I have just had dinner.
• A: Is Udit here?
  B: No, I'm afraid he has just gone.

👉I have already... (ALREADY = before you expected/before I expected)

• A: What time are Udit and Dipika coming?
  B: They have already arrived. (before you expected)
• It's only nine o'clock and Udit has already gone to bed. (before I expected)
• A: Udit, this is Dipika.
  B: Yes, I know. We have already met.

👉I have not ... yet / Have you ... yet? (YET = until now)

You can use yet in negative sentences and questions. Yet is usually at the end.

yet in negative sentences:

• A: Are Udit and Dipika here?
  B: No, they have not arrived yet.
• A: Does Dipika know that you're going away?
  B: No, I have not told her yet.
• Dipika has bought a new dress but she has not worn it yet.
• The film has not started yet.

yet in questions:

• Have Udit and Dipika arrived yet?
• Has Dipika started her new job yet?
• A: This is my new dress.
  B: Oh, it's nice. Have you worn it yet?

👉HAVE YOU EVER ... ?

We use the present perfect (have been / have had/ have played etc.) when we talk about a time from the past until now - for example, a person's life.

• 'Have you been to Australia?' (in your life)  'No, I have not.'
• I have been to India but I have not been to the Nepal.
• I have seen that woman before but I can't remember where.
• How many times has India won the World Cup?
• 'Have you read this book?'  'Yes, I have read it twice.'

👉Present Perfect + ever (in questions) and never:

• 'Has Udit ever been to Australia?'   'No, never.'
• 'Have you ever played golf?'   'Yes, I often play golf.'
• My grandmother has never travelled by air.
• I have never ridden a horse.
• 'Who is that man?'   'I don't know. I have never seen him before.'

👉Gone and Been:

• A: 'Where is Udit?'
  B: 'He is away. He has gone to NCR.' (=he is in NCR now.)

↓↓Two weeks later.↓↓

• A: 'Hello Udit.'
  B: 'Hello. I have been on holiday. I have been to NCR.' (=he went to NCR but now he is back.)

More examples:

• I can't find Dipika. Where has she gone? (=Where is she now?)
• Oh, hello Dipika! I was looking for you. Where have you been?

👉HOW LONG HAVE YOU...? (FOR / SINCE):

👉Present Perfect (I have done) AND Past Simple (I did);

With a FINISHED TIME (yesterday / last week etc.), we use the past (saw / arrived / was etc.)

past simple + finished time
We arrived	in 1987.
	last week.
	yesterday.
	four months ago.
	at 5 o'clock.

Do ㄨNOT use the present perfect (has / have etc.) with a FINISHED TIME.

• I saw Dipika yesterday. (not 'I have seen')
• 'What did you do last night?'   'I stayed at home.'
• We did not have a holiday last year. (not 'We have not had')
• William Shakespeare lived from 1564 to 1616. He was a writer. He wrote many plays and poems.
• Where were you on Sunday afternoon? (not 'Where have you been')
• When did they arrive? (not 'When have they arrived')

Summary => Present Perfect is Time UNTIL Now; Past Simple is Finished Time BEFORE Now.

More examples:

• I have lost my key. (Present Perfect)
  I lost my key last week. (Past Simple)
• Udit has gone home. (Present P.)
  Udit went home fifteen minutes ago. (Past S.)
  
• Have you seen Dipika? (Present P.)
  Did you see Dipika on Saturday? (Past S.)
• Have you ever been to Australia? (Present P.)
  Did you go to Australia last year? (Past S.)
• The letter has not arrived yet. (Present P.)
  The letter did not arrive yesterday. (Past S.)