-- _____is that used for?---_____ the floor.
____ he was fired by the company is ____ he didn’t work hard.
It is well known to us all ____ China sent up a manned spaceship to outer space successfully last year.
The players expected there ____ more free time before coming back to the country from abroad.
Word has come ____ some excellent students will go on a study trip to Chicago next month.
____ computers are of great benefit to the development of science and technology.