______ the Internet is of great help, I don’t think it is a good idea to spend too much time on it.
A. Unless B. Since C. When D. While
The first World Cities Day of the UN, _______on Oct.31, 2014 in Shanghai, focused on leading urban transformation.
A. to have been held B. having held
C. held D. being held
—You should take exercise in your spare time.
—I want to，but the little time I have outside of school is by part-time job.
A．taken away B．taken in
C．taken out D．taken up
The good thing about today’s children is that they can_____ very easily to new environments.
A. attain B. allocate C. adapt D. adopt
As a teacher, it is my _________ to make the students devoted to their study.
A. responsibility B. affection
C. performance D. judgment
The research lacks evidence，and therefore，its conclusions are doubtful.
A．solid B．fierce C．severe D．potential
