Another Latin course book gives information that does not agree with this course
First I am thinking about the word Num we have learnt here that it indicate a question with an expected NO answer (surely not) In my other Latin course book we are told that it only signals a question and is not translated. In the course book text are this sentence Num pater simiam ex Aeggypto affert, ut Marcus cupit ? According to course this should be translated Has the father brought (or with him) a monkey from Egypt like Marcus wishes ? (my translation swedish to english) No "surely not" meaning for the word num and ut meaning like. In duolingo translate I got this nonsensical result Num pater simiam ex Aegypto affert ut Marcus cupit Out of Egypt, to bring the father to the ape wants to, as Mark said,
What is the name of your book?
Rules are sometimes broken especially in conversation (early playwrights) or letters, but what you are questioning should hold true as a starting place for beginners. Notice the last sentence of the note in Gildersleeve and Lodge.
I presume that's also a good grammar.
What do you think about it?
Bennett's grammar is very easy to use and comparatively brief.--maybe more introductory and for quick reference, which is often all you need. Besides those already mentioned Harkness (cf. § 182, note 2) often has quite good explanations, as does Hale and Buck (cf. § 231.d). And there are plenty more Latin grammars that are also good, IMHO.
The course uses American English books which teach Latin a bit differently than in Europe. Here, num is used before sentences ending with a question tag, because it is used when a speaker wants a confirmation of a negative sentence.
For example: Livia mater Augusti non erat - Livia wasn't the mother of Augustus. Num Livia mater Augusti erat? - Livia wasn't the mother of Augustus, was she?
Compare it with nonne: Nonne Livia uxor Augusti erat? - Livia was the wife of Augustus, wasn't she? or Wasn't Livia the wife of Augustus?
Surely not is some obsolete phrase copied from some nineteenth-century book. Latin courses are mettled with such obsolete, grandiose-like expressions.
All the sources I can find in Italian agree that num introduces a question with no expected as an answer (unless it is an indirect question)...
Same for the several grammars I have checked in Russian and French. Just 2 examples:
The « Précis de grammaire des lettres latines » published by Éditions Magnard (1994) says for num in direct questions (§320):
num... ? / est-ce que...? | Num insánis? / Est-ce que tu est fou ? Est-tu fou ? | On attend ou on sollicite la réponse : / non
(num... ? / is it so...? | Num insánis? / Are you mad? | One expects or asks for the response : / no [the French question words do not attempt to translate the anticipated negativity, but it is made clear in the explanation])
And Sobolevskijs Grammar of the Latin Language (С.И. Соболевский, «Грамматика латинского языка») :
§ 846 Num употребляется тогда, когда спрашивающий желает указать, что он ожидает ответа
о т р и ц а т е л ь н о г о: неужели? разве?
(Num is used when the questioner wishes to indicate that he expects a negative answer: really? not really? [both Russian words are impossible to translate out of context])
Num quis est hic alius praeter me atque te? Nemo est (Plaut[us]. Trin[ummus]. 69) разве есть кто другой здесь кроме меня и тебя? Никого нет.
(... There isn't anyone else here besides you and me, is there? There is no one.)
Num negare audes? (Cic[ero]. Cat[ilinarian]. 1,8) неужели ты смеешь отрицать?
(... You don't dare deny it, do you?)
It could be that occasionally num is used "loosely" to simply introduce a question, just as, say, a double negative is sometimes used in English as a negative, but it doesn't sound like it was all that common in classical Latin.
Anyway, that's my shot at this question.
So to conclude it seem that the word signals a question with an expected No answer, and not only just a question. Could it be so that the question is not expected an definite or absolute certain no answer ? But maybe just some doubt about a yes answer ? I find it strange that authors of a course book in Latin for official use in school should get a thing like this completely wrong.
The only thing certain about num is that it signals a yes/no question for which the speaker expects a negative answer.
How you are going to translate such a question marker can be rather complex. A lot also depends on the language you translate to: as such, English text books might have different answers than your Swedish text book. Not translating num at all could be considered a valid option in some cases: often we do not indicate our expected answer to a yes/no question with more than a subtle tonal difference.
For example, the interrogative sentence "Are you going to the zoo?" might well be a neutral question or a question for which you expect the answer to be "no", depending on your intonation.