"Eu nu vorbesc în timp ce profesoara vorbește."
Translation:I do not speak while the professor speaks.
What's the difference between "while" and "at the same time" supposed to be here?
If you read the sentence as: "I do not speak, while (= whereas) the professor speaks", then in Romanian this would be Eu nu vorbesc, în timp ce (= pe când/ în vreme ce/ pe câtă vreme) profesoara vorbeşte.
On the other hand: "I do not speak while (= at the same time) the professor speaks" = Eu nu vorbesc în timp ce profesoara vorbeşte.
In Romanian, the key difference between the two functions of în timp ce (showing contrast and showing simultaneity) is in punctuation (the comma), as in the examples above. So far as I am aware, the same stands for while in English, but feel free to correct me if I'm wrong.