—I don’t think the headmaster knows who did it.—Well, surprisingly she does. A boy _____ in her office now.
The two Chinese scientists have made a wonderful discovery, which marks a major _______ in the basic research in the field.
The incident caused a hot discussion on the Internet, but the local government had no immediate _______ on it.
The young violinist is very excited because the concert given by him has never been _____.
______ enough time, he was full of confidence to finish the project.
Looking after very young children _____ be very annoying sometimes, but you’ll get used to it after a while.