On the 40th Earth Day, Dr Wang gave us a talk on the importance of ______ the earth.
| A．practicing | B．preventing | C．polluting | D．protecting |
He has lost his pen. He is _______ it everywhere.
| A．looking after | B．looking out |
| C．look like | D．looking for |
My mother told me _______ junk food at school.
| A．to not eat | B．not to eat |
| C．don't eat | D．didn't |
There 's a teacher _____ with your parents in the teachers' office.
| A．is talking | B．talks | C．to talk | D．talking |
That computer_____ me quite a lot of money.
| A．spent | B．cost | C．took | D．paid |
I never forget the days when I enjoyed ______ a good time in Beijing.
| A．have | B．to have | C．had | D．having |