"Are the bees flying out into the garden or the flies?"
Translation:A méhek repülnek ki a kertbe vagy a legyek?
Do the prefixes of all preverbs separate from the verbs in all interrogative clauses?
Yes, unless the verb is emphasised. In other words, if you want to know if an action happened or not, the prefix stays glued to the verb:
"A méhek kirepülnek a kertbe?" -- "Do the bees fly out into the garden? (Or not?)"
In this sentence (A méhek repülnek ki a kertbe vagy a legyek?) the question is who's the subject of the action (the bees or the flies?).
If you know that the bees are the ones to fly out, but you don't know if it's the garden they fly to, you can ask: "A méhek a kertbe repülnek ki, vagy máshová?" -- "Do the bees fly out into the garden or somewhere else?" The prefix is still separated from the verb.
But if the question is about the action itself (did/does/will it happen or not?), the prefix and the verb stay together: "A méhek kirepülnek a kertbe?" (Or do they stay inside?)
- "A moziba mész el?" -- "Will you go to the cinema? Or will you go somewhere else?"
- "A moziba elmész?" -- "Will you go to the cinema? Or will you stay at home?"
In that case, I wonder if a better English translation for the original sentence would be "Are the bees or the flies flying out into the garden?" The way it's worded, it sounds like the bees are either flying into the garden or into the flies.