Where are you? => Onde ficas?
Where do you go? => Aonde vais?
In Portuguese, that is true for the interrogative pronoun as well as for the relative pronoun, there is a distinction. We use onde, in case that we refere to a position and we use onde for a mouvement to a certain place we use aonde. In English we can use where in both cases.
A
casa
onde
nasci
vai
ser
recuperada.
The
house
where
I was born
goes
be
repared.
The house where I was born will be repaired. .
If a mouvement towards a place is described aonde is used.
O
lugar
aonde
ele
vai
fica
longe.
The
place
to where
she
goes
is
far.
The place she goes to is far away.
In some languages, german and french for instance, where / où / wo can refer as well to a period of time. (~The times where...). In other languages that is not possible. There is a third group of languages. In Portuguese the standard grammar rejects the use of where referening a period of time, but the use of where / onde is so common, that it seems that nobody cares about the standard grammar.
A sentence like that would be regarded as wrong.
Longe
vão
os
tempos
onde
cada
palavra
era
delicada,
pensada
três
vezes
antes de
ser
proferida.
Far away
go
the
times
where
every
word
was
delicate,
thought
three
times
before
to be
expressed.
The times when every word was critical, examined carefully before being used, are long gone.
Normative grammars tend to argue with logic, however logic is completely irrelevant in grammar rules. The use of where refering to a period of time or a moment is officially accepted in French and german and widespread used in Spanish. If it is so common in all languages than it is accepted by the human brain, it is the way the human brain wants to represent verbally the reality and that is the relevant issue, not "logic". This lady for instance just postulates that where can't be used in a context where it refers a to period of time, but she doesn't give any reason why that is wrong. We can call something an error if only a small group of people uses this construction and other people have problems to understand the structure. But if a constructon is used in almost all languages, if a construction seems "natural" to billions of people in different languages, the argument that this construction doesn't match with a "logic" is irrelevant.
Ana Paula teaches her students something, that their students shouldn't learn: To accept certain rules without questioning whether these rules make sense or not. This has nothing to do with Brasil, it is a common problem all over the world, but this is something that should be changed.
É um erro comum usar “onde” para se referir a não-lugares, aponta Ana Paula. “Os candidatos costumam jogar o pronome relativo onde em tudo o que é lugar. Porém, cuidado! Onde só retoma lugar", diz a professora. Caso o
aluno queira retomar um nome que não é um lugar concreto, o correto é usar "em que", "no qual", "nos quais", "na qual" ou "nas quais". ton 4
Widely spread is the error to use "where" in a context where it doesn't refers to places, says Ana Paula. "The candidates use normally where as a relative pronoun for everything that is a place. However attention! Where only refers to places", says the teacher. In case that the student wants to refer to a noun that is not a concrete place, "em que", "nos quais", "na qual", "nas quais" must be used.
Onde can be used as well with other prepositions like a, de, até, para and por. De + onde becomes donde and a + onde becomes aonde. (The Portuguese donde has therefore nothing to do with the Spanish donde. The Spanish donde is simply where, the Portuguese donde is used to descibe a mouvement, that woule be in Spanish de donde.)