When the students heard the news, all of them were in _____.
| A．higher spirit | B．high spirits | C．a high spirit | D．a higher spirits |
__________ not to gamble during the World Cup, those crazy people had to give up.
| A．Warned |
| B．Warning |
| C．Having warned |
| D．Having been warned |
Research __________ out by several experts suggests that the oil spill in the Gulf has caused the fatal damage to the environment.
| A．to carry |
| B．carrying |
| C．being carried |
| D．having carried |
My brother has always insisted on his __________ Tom instead of Tim.
| A．calling |
| B．called |
| C．having called |
| D．being called |
At the beginning of the class, the noise of doors__________ could be heard many times.
| A．opened and closed |
| B．to be opened and closed |
| C．being opened and closed |
| D．to open and close |
A simple 45-minute operation __________ by scientists is hoped to cure blindness in six years.
| A．being developed |
| B．developed |
| C．to develop |
| D．developing |