"The boy jumps out from the bed, from the top of which a pillow falls down."
Translation:Abból az ágyból ugrik ki a fiú, amelyikről leesik egy párna.
It is currently written as : "The boy jumps out from the bed [...]." But shouldn't "Abból az ágyból..." mean "The boy jumps out from that bed..." ?
Not necessarily. If we could just lose the comma in the English sentence, the meaning would be the same as the Hungarian one. But this is the least of the problems with this sentence, it is seriously weird. :)
The problem is, 'Abból az ágyból' is supposed to mean 'from that bed'. In order to learn Hungarian, it would be better to use slightly more literal translations. Now it's too arbitrary. You can never know whether the course creators expect 'from the' or 'from that'.
It can also mean "from the bed (which...)". That is, identifying which bed we are talking about. But yes, it is very difficult to guess what is expected. There is no easy way around it. I mean there is copy-and-paste, but, otherwise, unfortunately, there is too much that is lost in translation, it becomes a guesswork without context.