Copied from a previous comment of mine:
Danish utilises V2 word order which means that the finite verb has to come in the second position in a declarative main clause (= a main clause that isn't a question).
You see that in the following sentence, er comes in the second position: Vi er stærke.
If we add something in front of the sentence, the verb still has to be in the second position:
- Sammen er vi stærke.