1. Past simple
Present perfect
Talks about the past
NEVER connects with the present
Talks about the present
The events may have happened in the past, or started in the past, but it ALWAYS connects with the present

2. Past simple
Present perfect
I lost my keys yesterday.
I have lost my keys.

3. Past simple
Present perfect
I often played football in high school.
I have played football since high school.

4. Past simple
Present perfect
I lived in Santos for 10 years.
I have lived in SP for 10 years.

5. The golden rule:
If you mention WHEN things happened, it is ALWAYS a past simple action, NEVER a present perfect action

6. When...?
yesterday, last week/month/year, in March, in 2009, on April 7th, 10 minutes ago, between 2002 and 2004, at 3 p.m., last night, yesterday morning

7. Present perfect references
Recently, lately, since January, so far, just, already, yet
(usually, but not always) ever, never
For is possible with both the past simple and the present perfect tenses

8. In what situations should I use the present perfect?

9. Recent past actions / new information
I’ve cut my finger! It’s bleeding!
I’ve just finished this report.
I’ve got a new job.
[even if it happened a month ago, the first time I mention it to you I should use the present perfect]

10. With yet and already Have you finished that report yet?
Yes, I have already finished it.
No, I haven’t finished it yet.

11. Past experiences (which are still possible in the present, i. e
Past experiences (which are still possible in the present, i.e., they connect to the present)
I have been to England twice.
BUT I went to the Soviet Union twice.
I have never met Nicole Kidman.
BUT I never met Marilyn Monroe.
Have you ever ridden a horse?
BUT Did you ever go to Sobradinho?

12. Unfinished states / actions (they are still true now)
They’ve been married for 10 years
BUT They were married for 10 years (they aren’t married anymore).
I’ve worked for IPT for 2 years.
BUT Before that, I worked for Microsoft for 5 years.

13. Have you got everything so far?
Unfortunately, present perfect has an evil brother...
...you’ve been expecting this, right?

14. Present perfect continuous
I’ve lost my keys #
I’ve played football since = high school.
I’ve lived in SP for 10 years. =
I’ve been losing my keys.
(impossible, except with a different meaning)
I’ve been playing football since high school.
I’ve been living in SP for 10 years.

15. In what situations should I use the present perfect continuous?

16. To explain an effect I can see now
I’m hot because I’ve been running.
He’s wet because he’s been walking in the rain.
They’re dirty because they’ve been working in the garden.

17. How long have you been watching TV?
With how long?, since, for, to talk about actions (not states!) that started in the past and are still happening
How long have you been watching TV?
I’ve been studying for this test for weeks.
He’s been working in that project since last week.

18. Information that answers how much. and how many
Information that answers how much..? and how many...? questions is NEVER presented using present perfect continuous.

19. To talk about continuous actions which have just finished, with present results
It started raining this morning and it rained for the whole afternoon. It stopped raining 10 minutes ago, but the ground is still wet. ↓
It has been raining.