There are various grammatical means in Danish to indicate, that some event or state of affairs took place in the past. But these means vary in terms of the viewpoint, or aspect, that they express. Here, we’re going to focus on the distinction between past tense and present perfect (aspect).
The past tense indicates the specific past time when an event took place, as illustrated in the examples in (1). That specific time must be either expressed explicitly as in (1a) or simply be known to speech participants as part of their shared knowledge as in (1b), or evident from context as in (1c-d).
(1) a. Jeg var til koncert i weekenden ’I attended a concert over the weekend’
b. Vi gik også på restaurant ’We also went to a restaurant’
c. Hvem bankede på døren? ’Who knocked on the door?’
d. Gav du pizzamanden drikkepenge? ‘Did you tip the pizza guy?’
The present perfect, on the other hand, indicates that an event or state of affairs has taken place in the past and also has current relevance at the time of speech. Unlike the past tense, it does not focus on the specific time when it took place. Current relevance can take the form of noticing, discovering or conveying new information as in (2a-b) or as part of the accumulative experience of speech particpants as in (2c-d).
(2) a. Nogen har drukket min mælk! ‘Somebody has drunk my milk!’
b. Din plakat er faldet ned igen ‘You poster has fallen down again’
c. Jeg har været i Indien mange gange ‘I’ve been to India many times’
d. Hun har arbejdet her i mange år ‘She’s worked here for many years’
As evident from (2) it is not relevant whether or not the event or state of affairs is finished at the time of speech, nor how long it lasted, or has lasted, nor whether it happened quickly or suddenly or had some duration. The crucial factor is current relevance at the time of speech.