How would you say "they never do anything"? Google translate suggests "oni nigdy nic nie robią", but "they never do nothing" translates to the same thing, which is opposite in meaning. Should I be saying "they never do something" instead? i.e. "oni nigdy czegoś nie robią" Thanks!
I'd go with "Oni nigdy nic nie robią" because it avoids putting the pronoun "nic" at the end of the sentence. But "Oni nigdy nie robią nic" could also work if you wanted to emphasize the 'nothing, absolutely nothing' part.
"Oni nigdy czegoś nie robią" is fine grammatically, but very strange semantically (just like in English, I believe) - "So there's one thing that they never do, but what was that, I cannot remember... anyway, they never do something".