"Are you afraid of ghosts?"
Translation:Bạn sợ ma không?
'ghosts' is plural. This translation for 'ghost' is singular. Share your vietnamese expertise please
Caveat: I'm not a native speaker. But how I think I understand it is that since this is asking about being afraid of ghosts in general, rather than a specific number of specific ghosts, pluralization is not required in vietnamese like it often is in English to refer to something in general.