The Helper Verb "er"
In Danish, the present perfect tense usually uses the helper verb har (have/has). However, there is a very important exception: verbs that describe motion (moving from point A to point B) or a change of state use er (am/is/are) instead.
When you talk about travel, departures, and arrivals, you will literally say that someone or something is landed, rather than has landed.
| The plane has landed, but it is often delayed. | Flyet er landet, men det er ofte forsinket. |
This rule applies to all verbs focused on arriving or moving to a destination, such as ankomme (to arrive) and gå (to walk/go).
| The train has not arrived at the platform because the departure is delayed. | Toget er ikke ankommet til perronen fordi afgangen er forsinket. |
| Why has the passenger gone to the platform? | Hvorfor er passageren gået til perronen? |
Moving Away and Changing State
When describing departures, you will often see verbs of motion paired with the phrase af sted (away / off). Because movement is involved, you must still use er as the auxiliary verb.
| The ship has sailed off because the captain is ready. | Skibet er sejlet af sted fordi kaptajnen er klar. |
| The bird has already flown away. | Fuglen er allerede fløjet af sted. |
Just like motion verbs, verbs that describe a sudden event or a change of state—like forsvinde (to disappear) or falde (to fall)—also take er in the present perfect.
| The captain has left, and he has disappeared. | Kaptajnen er rejst, og han er forsvundet. |
| The boy has fallen into the lake, but he has not disappeared. | Drengen er faldet i søen, men han er ikke forsvundet. |
