It's time I __________ home. My mother should be waiting for me for dinner now.
| A．return | B．must return |
| C．returned | D．will return |
______ 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 isby 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 |