They make butter from milk поставить в пассивный залог

To put the phrase "They make butter from milk" in the passive voice in Russian, you can say: "Масло делается из молока." This construction transforms the active sentence into a passive one where the focus shifts from the doer of the action to the action itself. The verb "делается" is the passive form of "делают" (make) in this context, and "из молока" remains unchanged, meaning "from milk." This passive voice construction in Russian emphasizes the process of making butter rather than the specific actors involved in the action.