——Why did you not come to the party? ——I ______ it, but my car broke down on the way.
Time should be made full use of _________ ourselves.
Electricity ,like other forms of_________ ,has greatly increased in price.
In the good care of the nurses, the boy is _________ recovering from his disease.
Ladies and gentlemen, please fasten your seat belts. The plane ________.
The chairman thought ________ necessary to invite Professor Smith to speak at the meeting.