I'm here in the politics lesson - so, of course, I used "regime" instead of "diet" - WRONG :/
you are on a diet is also a good translation, i think.
That would be correct if the sentence did not have a question mark at the end of it. The ? alters the phrase from a statement of fact (You are on a diet) to a query (Are you on a diet?).
Depending on how it's said in English (usually raising the voice at the end), "you are on a diet?" can be made into a question.
I shall say that it is common anyone say “cê tá” than “você está”, here in Minas Gerais and in the other regions they say it
Are those valid alternatives?
Yes, they are both right.
Is Dieta not used more frequently than Regime in Brazil for this meaning?
Does this translate directly to "You are of diet?" Is there a way to say this in Portuguese that would make more sense to an English person? I don't think I can remember this.
How does "de" translate to "on a" ?
Doesn't De usually mean Of or From?
General question: from the audio on Duolingo there is no cue when this phrase is a statement or a question. Without reading the punctuation there is no way I can discern a question from a statement. Am I missing something?
Unless your sentence continues with, As you look great use this phrase sparingly
You are dieting? Is also rejected.
I hear the word "regime" as "hedgimmy". How is it pronounced in European Portuguese?