______we were worried about was ________they could manage to control the pollution.
| A．That how | B．That whether | C．What that | D．What whether |
【2015·陕西】After receiving the Oscar for Best Supporting Actress, Anne Benedict went on ______all the people who had helped in her career.
| A．to thank | B．thanking |
| C．having thanked | D．to have thanked |
【2015·天津】______in painting, John didn’t notice evening approaching.
| A．To absorb | B．To be absorbed |
| C．Absorbed | D．Absorbing |
【2015·天津】______ for two days, Steve managed to finish his report on schedule.
| A．To work | B．Worked |
| C．To be working | D．Having worked |
Listening to music at home is one thing, going to hear it ______ live is quite another.
| A． | perform | B． | performing |
| C． | to perform | D． | being performed |
【2015·重庆】Like ancient sailors, birds can find their way____ the sun and the stars.
| A．used | B．having used | C．using | D．use |