"What is impossible?"
Translation:Hvad er umuligt?
Now I am not completely sure, and I just went through, like, 25 adjectives in my head just to try to answer your question....but we use the -t ending for questions like these, beginning with "hvad". However, when using "hvem" (who) then it's without the -t.
- "Hvem er smuk?", "hvem er blå?", "hvem er sød?" (Who is beautiful?, who is blue?, who is sweet?) as opposed to
- "Hvad er smukt?", "hvad er blåt?", "hvad er sødt?" (What is beautiful?, etc)
And as always, there are exceptions.