"I do not see any window."
Translation:Non vedo nessuna finestra.
I'd think it shouldn't have... It looks like nessuna is used in negative sentences.
Niente is translated to nothing in English. So, when this happens, you are basically saying, "non vedo niente finestra" ,which translates to "I don't see nothing window". This is technically grammatically incorrect.
So, by doing this, you imply, "nessuna=any", for the response. Thus, making this sentence grammatically correct.
What's that supposed to be? As a translalion for any they propose qualsiasi or communque. Yet they reject it as valid, they want alcune. And then they give nessuna at the top.
Qualsiasi only translates as "any" in a positive sense. You may like to check my discovery of this on Duolingo at http://duolingo.com/#/comment/231470?from_email=comment
The English translation is grammatically wrong. The word "ANY" is used with plural nouns and uncountable nouns. As the window in this example is a countable noun, the translation should be "any windows". I reported it.
Do you have to use a double negative in Italian or is it just acceptable? If I just said "Non vedo una finestra" would that be considered incorrect?