A. Study this example situation:
Tom is looking for his key. He can’t find it. He has lost his key.
He has lost his key = he lost it and he still hasn’t got it.
We use the present perfect when we talk about a time from the past until now — for something that started in the past and continues to now, or for something that happened in the past and affects the present.
B. Present perfect = have/has + past participle
| I/we/you/they | have (= I’ve etc.) | done been seen etc. |
| he/she/it | has (= he’s etc.) |
I have lost my key. (= I don’t have it now)
‘Where’s your key?’ ‘I don’t know. I have lost it.’
Sarah is looking for her phone. She has lost it.
‘Have you seen my phone?’ ‘No, I’m sorry. I haven’t seen it.’
C. We use the present perfect for actions in the past which have a connection to now:
I have done a lot of work today. (from morning until now)
We have eaten all the eggs. (there are none left)
Have you ever been to Japan? (in your life, up to now)
I have never seen snow. (in my life)
D. Compare present perfect and past simple:
Present perfect: I have lost my key. (I don’t have it now)
Past simple: I lost my key yesterday. (we know when)
Present perfect: Have you ever been to Japan? (in your life)
Past simple: I went to Japan last year.
Past simple → UNITS 5–6
Present perfect + ever/never → UNIT 33
Examples
He has lost his key.
I have lost it.
She has lost her phone.
I haven’t seen it.
I have done a lot of work today.
We have eaten all the eggs.
Have you ever been to Japan?
I have never seen snow.
I lost my key yesterday.
I went to Japan last year.