Past simple vs Present Perfect
Past simple: is finished and you know when it happened.
yesterday, last week, a month ago, in 1990, etc...
Ezelsbrug: LADY (last, ago, date, yesterday)
Present perfect: (1)just finished / you notice the results now, (2)still going on now, (3)experience, (4)don't know when it happened.
Signaalwoorden: for, yet, never, ever, just, already, since, lately
Ezelsbrug = FYNE JAS