1 I am reading an interesting book at the moment (4 предложения)
What are you doing at the moment?
What are you reading?
What book are you reading?
Are you reading or watching TV at the moment?
2 She is taking a bath (2 предложения).
What is she doing now?
Is she taking a bath or a shower?
3 I am trying to concentrate (2 предложения).
What are you doing now?
Why are you trying to concentrate?
4 I am looking for my keys (3 предложения).
What are you looking for?
Whose keys are you looking for?
Are you looking for your keys or for your bag?