难道‘nándào’ (Is it possible…): The adverb is used in a rhetorical question to reinforce the effect of the question, it expresses the speaker’s judgment that what is heard is ‘surprising’ or ‘unbelievable’. Sometimes, the speaker uses a rhetorical question to express his viewpoint, as in (1b):
Nǐ yǐjīng qùguò sāncì Zhōngguó, nándào méi qùguò chángchéng ma?
(You have been to China three times, is it possible that you’ve never been to the Great Wall?)
Nǐ néng qùnándào wǒ bùnéng qù ma?
(Yu can go, why can’t I go?)
 Loar, J. K. (2011). Chinese syntactic grammar: functional and conceptual principles. New York: Peter Lang.