21.—It is said that he is focusing on another book on space exploration. When will it come out?
—It is _______ next year.
A. about to be published B. surely to be published C. due to be published D. going to publish
22.We were stuck at the airport because of the heavy fog, otherwise we ________ here in time for the conference.
A. arrived B. had arrived C. would arrive D. would have arrived