Why isn't "silly" accepted as a translation for "hloupé"? It's in my Czech-English dictionary, and I'm used to this meaning.
It was currently accepted in certain forms, but not in all of them, so I fixed that now.
I wrote, "You are not supposed to talk about such stupid things," and it was marked wrong. Ale je opravdu OK?
If mám as a modal means "I ought" then why doesn't nemám mean "I need not" (I'm under no obligation to.) Here it seems to mean that you do have an obligation to refrain from action.
Indeed, you do have an obligation not to do it.
Why? These questions hardly work for natural languages. Why is mustn't not the exact opposite of must?
I agree, that the recommended sentence translates the meaning. But I think it [the Czech sentence] neither contains "should" nor "such". In other examples you used "can"[not] and "so" for both words. Can you please explain, when I have to take "can", "be suppoed to" or "would/should" ?