"Yes, you speak Romanian."
Translation:Da, vorbiți limba română.
We have three options for translating "We speak Romanian." All three are correct and common.
I. "Vorbim româna" = We speak Romanian. (Româna is the name of the language. Grammatically, it is a noun.)
II. "Vorbim limba română" = "We speak the Romanian language."
This is a useful construction if, for example, you want to say: "Vorbim limba română nu limba germană." You can also say "Vorbim româna nu germana."
"Vorbim limba română" adds more emphasis and is a bit more formal, but it doesn't contain more information.
III. "Vorbim româneşte."
"Româneşte" is an adverb. "Vorbim româneşte" still means "We speak Romanian." The verb "vorbim" allows the use of an adverb like "româneşte" but also the use of a noun like "româna" because it is a transitive verb (all transitive verbs allow the subsequent use of a noun without a preposition).
So, the difference is technical (i.e., grammatical).
Vorbim româneşte = Transitive Verb + Adverb
Vorbim româna = Transitive verb + Noun (direct object).