Some time after the rockets and the space shuttle are _____, the rocket will _____ the space shuttle and ____ the sea.
______ you do the experiment carefully, you would make discoveries others wouldn’t make.
We had to the match as the ground was too wet to play on.
It was 1995 __________ we began to develop the new computer system.
He is _________ to have gone abroad,for I haven’t seen him for weeks.
As a teacher, I seldom give my students so difficult a problem_______ they can’t work out.