"Is forbidden to jump here." was not accepted but "It's forbidden to jump here." is accepted. Sorry if its a bit off topic but can someone tell me a bit about this english rule so I can research more about it myself?! I'm can't tell the difference between these two sentences.
Thanks for mentioning the gerund! Both sentence versions make more sense now. https://www.englishclub.com/grammar/verbs-gerunds_1.htm
"Prevented" (не допущено ) may be translated as 'not allowed' (нельзя), but in this particular sentence the word 'нельзя' means "forbidden', which is not completely the same as 'prevented'. For example, if you visit a construction site, the sign there might say that entrance is forbidden, but it can't physically prevent you to enter...
p.s. please don't try this example at home! ;-)
@Sardinius - In your sentence, "Jumping" is a noun and should therefore go at the beginning of the sentence ("Jumping is not allowed here"). If DL doesn't accept that version then it should be reported to the mod staff for consideration, because it is just as good as "It is not allowed to jump here".