The comments remind me of the constant efforts by parents to help their children distinguish between "may I?" and "can I?" The first involves permission and the second involves capability.
Is can I/ can we a possible translation, as in the similir question with אפשר?
Not quite, because זה מותר means it is allowed generally, to anyone, not just to me.
'This is allowed?' Does this mean anything different from 'Is this allowed'?
"This is allowed.", is a statement in written English. "Is this allowed?", is a question in written English. If someone said out loud, "This is allowed?", to make it a question they would have to modify the tone of their voice to make it sound like a question.
Grammatically yes, but the actual meaning is the same.
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