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.
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" ?
If you want to use "so," the word order needs to change. You could say, for example, "You should not say things so stupid!" That is an accepted translation. Compare:
Ex 1 - You should not say SUCH stupid things.
Ex 2 - You should not say things SO stupid.
In Ex 2, we sort of insert an imaginary phrase to get, "You should not say things [imaginary phrase: that are ] SO stupid.
I hope this makes some sense... :-)
BoneheadBass, there is no reply option on your statement, so I'm responding to the parent message. "You should not say things so stupid" doesn't sound right to me. It feels either incomplete or grammatically incorrect. I feel like in order for "so" to work in this location, it should either be, "You should not say things that are so stupid" (i.e., that are is not optional and using the "such" construct is much more concise) or, "You should not say things so stupidly" which has a different meaning.
@PritelBobka, I don't disagree that "You should not say things that are so stupid" is a solid sentence, but it (IMO) is not ideal as an accepted translation of the Czech sentence, as there is nothing in the original that would become "that are." Hence my reference to the inserted "imaginary phrase" which you have made explicit.
In any case, at least as of six months ago, "You should not say things SO stupid" was accepted. The team may or may not feel it should be removed, or that your more explicit version should be added. :-)