Special attention should be paid _______ our earth from _______.
| A．to protect; being polluted |
| B．to protecting; being polluted |
| C．to protect; polluting |
| D．to protecting; polluted |
----- You seem in low spirits. Anything wrong?
----- I ______ in the important exam. I let my parents down.
| A．fail | B．failed | C．has failed | D．had failed |
A wallet has been found and can be ______ the manager’s office.
| A．claimed | B．announced | C．declared | D．cheered |
----- How did you know the surprising news?
----- I happened _______ the event then.
| A．to cover | B．to be covering | C．covering | D．to have covered |
If the wound ______ become infected, do not hesitate to call me.
| A．shall | B．must | C．should | D．would |
With two sons ______ in Afghanistan, John and Susie Mayes are working extra hard this year to make sure their grandchildren have a great Christmas.
| A．to serve | B．serving | C．having served | D．served |