Ann is sining a song now.
1) Is Ann sining a song now?
2) What is Ann sining now? Who sining a song now?
3) Ann is sining a song now, isn't she?
4) Is Ann or Jane sining a song now?
My friends live in Moscow.
1) Do my friends live in Moscow?
2) What do do my friends in Moscow? ( do и do должны повторять так как первый do - это вспомогательный глагол, а под вторым do подразумевается, что они делают там)
Who lives in Moscow?
3) My friends live in Moscow, don't they?
4) Do my friends or my parents live in Moscow?