In September 2008,China’s key milestone in space travel _____when Zhai Zhigang conducted the first space walk.
The income of skilled workers went up. ________, unskilled workers saw their earnings fall.
After dinner he gave Mr. Richard ________ ride to ________ Capital Airport.
He got well-prepared for the job interview, for he couldn’t risk the good opportunity________.
Only teachers are permitted to enter the reading room, that is to say, the reading room is only________ to teachers.
I’m as busy as a bee; ________ you bother me with so many questions now?