"Ella va" can mean "she goes", "she is going", "she does go" just like "yo hablo" means "I speak", "I am speaking" and "I do speak" . It only accepts "She goes" as the correct answer however.
Actually, "to be doing smth" is translated with estar+ verb in gerund form ("-ando"), that is "esta hablando". The form with auxiliary verb do, to highlight that something actually happened or was done, is translated differently, sometimes it's just stressed by the tone of the voice.
You are correct in the literal sense. However, in Spanish and most any language one tense will often have more than one use or meaning. For example, the present tense in Spanish can also be used at times in place of the future tense i.e. "Hablo con ella mañana " (I am speaking with her tomorrow [literally "I speak with her tomorrow] ) This is the present tense but used as a future one.
"Estoy hablando con ella " and "Hablo con ella " can both mean "I am speaking with her " . If you are using the present progressive (-ando) however most of the time it means you are actually doing the action right at that moment .
There are many times with duolingo that it has used the present tense and translated it as actual doing something at that moment, which is correct based on context. This is one of the times it has counted it wrong however. If someone asked "¿Dónde está tu esposa ahora mismo? " (Where is your wife right now) I could say both "Vuelve a la casa" and "Está volviendo a la casa" and both could be translated as "she is returning home " There are a zillion other ways I could say that too, but language is such a flexible dynamic entity I can't expect a program such as this to always accept every correct translation.
I love duolingo by the way. I think it's the best iPhone/iPod app out there for learning a language, and it's fun !
That happened to me in Turkish, which is my native language. But then I thought the program wants you to focus on the subject you are testing or learning. So that should give you a hint about the answer beforehand.
By the way it is great to know 1 tense practically means more. See! Checking comments are great for details. It's an important part of duolingo. Thanks!
What you said was nearly correct, but not always the Spanish present simple can be translated as the English present continuous.
For instance, the "vuelve a la casa" answer is incorrect. the sentence is gramatically correct but odd to a native speaker for that kind of question; "está volviendo a casa" is correct and even we can drop the verb to be and make a shorter sentence: "volviendo a casa".
It sounds like it's between a 'b' and a 'v', so it would be a bilabial fricative - I think it's voiced, too. If you're really interested: http://en.wikipedia.org/wiki/Voiced_bilabial_fricative
I also listen to the "Notes in Spanish" podcast, and it sounds like it's between a 'v' and a 'b' also, so it's not just this recording.
Sorry people, but this section is so badly handled it is doing more damage then good ... the table in the explanation is 3 column, when it should be FIVE!!!! A column for each type of verb in the exercises so that it will eliminate the guess work and the pain of unlearning wrong preconceptions ... FIX IT!!!
Perhaps "She" may go, but going where you may ask? Perhaps in one of the compass rose directions. North, East, South, or West? We may perhaps never know. Or maybe the cardinal directions? Northeast? Northwest? Southeast? Southwest? We will likely never find out where she goes.