"We have lived together for twenty years."
Translation:Мы прожили вместе двадцать лет.
Yes but "has done" refers to a completed action, whereas in this example the English sentence is continuous in meaning. You would say it if you still live together. If you no longer lived together it would be "lived" not "have lived". Doesn't the suggested translation suggest you are no longer living together?
Based on the English prompt, the corresponding Russian is incorrect. "Have lived" puts us in the present, so the Russian verb should be present. If жили is the base, then you're right "lived" or "had lived" would be correct. If we say in English "i have lived/have been living in America for ten years" it's "я живу в Америке 10 лет".
"Я прожил в Америке 10 лет" may mean two things: (1) "I have lived/have been living in America for 10 years" (same as "Я живу в Америке 10 лет") and (2) "I lived in America for 10 years (but then moved to another country)". You can't really tell from the Russian perfective past of verbs with the про- prefix whether the action/state continues into the present or not.
Please don't get me wrong here; I think I must make a caveat. What I said about perfective verbs starting with про- is only valid in the context where the verb has as its direct object a phrase referring to a time period (e.g. "прожил два года", "прождал вас полчаса", "проторчали там неделю", "проспал полдня", "просидел в тюрьме пять лет", and similar phrases with verbs пробыл, пролежал, провалялся, простоял, провисел etc.). Outside of such a context Russian, perfective verbs starting with про- always refer to the past when used in the past tense. For instance, if you say "Прошел дождь" (It rained for a while), you only inform someone that the rain started and finished, and if you say "Дождь уже прошёл" (literally, the rain has passed by"), it just means "The rain is over / It's not raining anymore". With transitive verbs the prefix про- can add other meanings such as 'through' or 'break' - прорезал = cut through, проломил = broke (a wall, smb's crane), прожёг = (burnt through, продавил = forced in - or the meaning 'from beginning to end' / 'thoroughly' / 'completely', e.g. Мы проговорили все детали. With some verbs (e.g. прочитать) the prefix про- doesn't add any meaning beyond making the verb perfective.
Interesting, thanks. You know I was actually just reading about how Russian scholars of the 19th C rejected the idea that Russian had any tense at all, that the -л form for the past tense is historically a deverbal adjective or past participle. Modern scholars disagree of course, but it's still an interesting idea, especially given your comment about whether or not the perfective про- prefix continues from the past into the present.
I would say "мы уже двадцать лет живём вместе" and it would be equivalent to the English "we've been living together for twenty years already". It's perfectly normal and should be accepted IMO.
Lokillo888, yes, you can say that, although the word "проживать" sounds somewhat official, so it would be okay in legal context, but in less formal cases it's better to use "жить".
I've entered to ask roughly the same. Can't we say?: Мы проживаем вместе уже 20 лет?
"мы живём вместе двадцать лет" should be accepted. Duo's solution "мы жили вместе двадцать лет" would be translated into English as "We had lived together for twenty years."
We have lived together for twenty years, and are planning on continuing. Mы живём вместе двадцать лет, и планируем продолжать.
We had lived together for twenty years, until she died. Mы жили вместе двадцать лет, пока она не умерла.
The verb сожительствовать is used by people who frown upon relationships without marriage. So it is unlikely that the speakers apply this verb to their own relationship. Also, state verbs in the Present Perfect are never translated into Russian as imperfective verbs in their past tense form.