Please remain ________；the winner of the prize will be announced soon.

Some people hold the view that the new machine is advanced, while others are still skeptical _____ whether it is of practical use.

Although taking wedding photos has become more popular among graduating students, many students        _______it requires both money and courage.

Please put away your clothes hanging outside. As you know, dark clouds______ heavy rain.

If you are feeling so tired, perhaps a little sleep would____．