"The juice is ours."
Translation:O suco é nosso.
That's European Portuguese, which is not what is being taught here.
Thank you for clearing that up. My thesaurus confuses me more than it helps me sometimes.
Would "O suco é o nosso" also be correct here? I'm still a little fuzzy on when the articles are optional and when they aren't.
Can't help you with any rules, but you wouldn't say that. Probably because "suco" and "nosso" refer to the same thing, so you're repeating the article for no reason. However, if you were pointing out your juice from other people's juices, you would say "This is ours" > "Este é o nosso", "o" not being mandatory, but most naturally to be used here.