"Are you an engineer?"
Translation:Te mérnök vagy?
'Vagy mérnök?' is wrong indeed. In this question the verb is either at the end or is omitted (from the end), but not at the beginning of the sentence.
(Én) Mérnök vagyok? (Te) Mérnök vagy? Ő / Ön / Maga mérnök?
(Mi) Mérnökök vagyunk? (Ti) Mérnökök vagytok? Ők / Önök / Maguk mérnökök?
Note that in the 3rd persons the verb is omitted - and this is compulsory.
But "Ön mérnök?" is accepted, while "Té mérnök?" is not. How are we supposed to know when the verb is required and when it's prohibited?
I'm just a learner, but this rule is one of the first ones in all the hungarian learnbooks: HE, SHE, IT (O") does not require any "to be" verb.
I am a human. Ember vagyok.
You are a human. Ember vagy.
He is a human. O" ember.
We are humans. Emberek vagyunk
You are humans. Emberek vagytok.
They are humans. O"k emberek.
Many logical constructs defy logic - you just have to remember them (e.g., by using them often).
Ön is a more formal and polite way of addressing someone than maga. You would not say maga to your teacher. If a police officer addresses you with maga you can warn him/her to be more polite.
Note that there is a third formal 3rd person pronoun: kend (perhaps not essential in an A1-B1 course). Kend used to be the way of addressing the lower party in an asymmetric relationship, but has mostly died out.
Someone, please help me, I am confused on usage of Te and Ön. In this example "Are you an engineer?" - Te mérnök vagy? - "You" is translated as "Te". However, just a few cases before, "You are sales lady" was translated as "Ön eladó". I understand in Hungarian there are informal "you - te" and formal "you - ön", but how do distinguish those in English?
There's no way to distinguish them in English. Duo should accept both te and ön when you are translating from English into Hungarian. In some cases, you can't even tell the difference between singular ang plural "you" in English, so the plural versions ti and önök may be accepted as well.