Present perfect or simple past tense

Present Perfect or Simple Past?

How to choose between the Present Perfect and Simple Past Tenses

  • Always use the Present Perfect when the time is not important, or not specified or when we more interested in the result than in the action itself.
  • Always use the Simple Past when details about the time or place are specified or asked for.
Present Perfect Simple Past Simple
Unfinished actions that started in the past and continue to the present:
  • I've known Julie for ten years (and I still know her).
 Finished actions:
  • I knew Julie for ten years (but then she moved away and we lost touch).
A finished action in someone's life (when the person is still alive: life experience):
  • My brother has been to Mexico three times.
 A finished action in someone's life (when the person is dead):
  • My great-grandmother went to Mexico three times.
A finished action with a result in the present:
  • I've lost my keys! (The result is that I can't get into my house now).
 A finished action with no result in the present:
  • I lost my keys yesterday. It was terrible! (Now there is no result. I got new keys yesterday).
With an unfinished time word (this week, this month, today):
  • I've seen John this week.
 With a finished time word (last week, last month, yesterday):
  • I saw John last week.

Compare:

Present Perfect Simple Past

I have lived in Lyon. (exprerience)

I lived in Lyon in 1989. (finished action)

They have eaten Thai food. (exprerience)

They ate Thai food last night. (finished action)

Have you seen 'Othello'?.

Where did you see 'Othello'?

We have been to Ireland.

When did you go to Ireland?

There is also a difference of attitude that is often more important than the time factor.

  • "What did you do at school today?" is a question about activities, and considers the school day as finished.
  • "What have you done at school today?" is a question about results - "show me", and regards the time of speaking as a continuation of the school day.