Just to expand on this... take note of the inversion. Danes invert subject and verb when some structural component of the clause occurs before the subject fx. "Altid drikker jeg øl". The inversion doesn't happen after a conjunction, however fx. "Det regner men jeg er hjemme"
Yeah, in English "however" is a special word with funny punctuation. Technically, it's only correct to use it at the beginning of a sentence, followed by a comma, such as "However, they still ate there." or you can also use it like this: "We went to the market; however, they were out of carrots."
Some more examples of other conjunctive adverbs and their usage is here: http://www.talkenglish.com/Grammar/conjunctive-adverbs.aspx
You are correct, the word can also translate to "at the same time"
I know that "They are, however, the same" is the answer that Duolingo wants. That's a very stiff way of putting things in English, though (That is, however, a very stiff way of putting things...). I can imagine such a thing being said in a court of law, but hardly in natural conversation. I think that "They're the same, though" should be accepted.
Hmm. I don't see any grammatical incorrectnes here. Consider the following sentences:
-- However, they are the same.
-- They, however, are the same.
-- They are, however, the same.
-- They are the same, however.
Which of these formulations one chooses to use is a question of style and of emphasis. Grammatically, however, they are all perfectly correct.