"Where do your sisters go?"
Translation:Onde suas irmãs vão?
In my daily speech, I usually say "onde", giving more freedom to the responder to use whatever preposition they wish. I have always seen "aonde" as a contraction of the preposition "a" with the interrogative pronoun / adverb "onde". So, I tend to use "aonde" when there is a notion that the preposition "a" will be necessary in the question, or is required by the rest of the statement in a non-question. For example, "o lugar aonde ele foi é mais bonito que o lugar onde ele nasceu". Notice that the first "aonde" implies movement to some place, the other merely denotes the place where an event happened.
Now, "Ir" is a verb that often takes the preposition "a", with the meaning of "going to some place". And so, questions that ask for this meaning could start with "aonde". But that is not the only case. For example:
"eu vou AO teatro" = "eu vou a + o teatro" says where someone is going to, and can rightly be asked by "aonde"
"eu vou DE carro" describes my mode of transportation, and the right question would be "como vais [para lá]?"
"eu vou PARA a escola" is different from "eu vou à escola". This last one is the same case as "ao teatro", it just takes a feminine noun and so we have the contraction "a + a = à", between a preposition and a definite article. The right question is still "aonde vais".
But the first phrase, "eu vou para a escola", or by the way, "eu vou para o trabalho", suggests a much more permanent change. It's what we say in the morning when we leave house to some place where we'll stay for hours, until we come back in the evening. "eu vou à escola" suggests I could go there, stay for a while to do some short errand and then come back. It also suggests a regular habit, something I do every day (and probably would be complemented by some explanation about that school, like "eu vou à escola no bairro onde vivo", or "eu vou à escola três vezes por semana". But now, it would not be right, in my point of view, to ask "aonde vais" if the right answer is "eu vou PARA algum lugar", or for example "eu vou para aquele sofá". Of course, we could ask "para onde vais".
What I think, though, is that if we use one of these prepositions in the question we are restricting the possible answers, which might not always be appropriate. For example, if I leave the house but my friend does not know what I'm going to do, he might just ask "onde", and let me decide if the answer is worthy of "a" or "para.
Incidentally, in BP there seems to be another preposition use with "Ir" which does not exist in EP: "eu vou NO teatro", with the preposition "em". And then, to be logical, the question would have to include "em" and not "a". In EP, that is just bad.
I think the more natural order (the only one, actually) in Portugal definitely is "onde vão suas irmãs". Actually, that would even be "onde vão as tuas irmãs". The general rule in questions, in several languages (french, german and also non-brazilian portuguese) is to invert the verb and the subject. African portuguese is more similar to the european one, that's why I made the distinction.
I agree. I said the general rule. I heard from a native French that they still learn in school to change the order of the verb, but that they don't do it often. Strangely, in Portugal, we sometimes do it, we sometimes don't, depending on the structure of the phrase. For example, we can easily ask "tu já fizeste o prometido?", but it does not seem proper in EP to say "onde tu vais?". I think with interrogative pronouns we always invert the verb, now that I think of it. It's just too awkward not to do it. We also use something like the French "est-ce que" (it's been ages since I used this!): "onde é que tu vais?" is perfectly normal in EP.
The verb "(eles/elas) andam" is the same as "(they) walk". In this case, the verb "to go" is "ir": "they go" is "eles/elas vão". But the "onde" is incorrect. The correct is "aonde" or "para onde". Duolingo is wrong. Ex.: "my sisters go TO _". The "a" and "para" before "onde" means the preposition "to" in english.