Proposal: Arabic language (اللغة العربية)
Requests for a translation are explicitly off-topic on all Stack Exchange language sites, for the obvious reason that Stack Exchange is not a free translator service. Similarly, simple word translations are frowned upon, as these can be handled by a dictionary.
should be acceptable.
Less likely to be left open are confirmations that a given translation is correct, especially if this is part of a formal learning course or for non-personal use, but that's up to the community to decide, where its boundary will be.
I'd say if OP is addressing a meaning of a word or an expression it should be on-topic, as one could assume that the questioner has done some effort before to understand the sentence or meaning of a paragraph.
For example I've encountered the following sentence:
Now I'd like to know the meaning of the expression "X" ...
But for example translating a whole text or sentence should not be on-topic, as this might end up as an opinion-based answer. For each word or expression you'll already find a couple of synonyms, translating a sentence or more would be too extensive with only small benefit!
Also note that translating questions would show no own effort in finding a solution.