When about one of the biggest problems today, many experts say that an energy crisis is approaching and is thus threatening mankind's survival．
| A．asked | B．being asked | C．having asked | D．asking |
When copying the paper，be careful not to ________ a single word.
| A．leave out | B．come out | C．begin with | D．come up |
Forty people got injured in a bus accident. Every ________ ambulance was rushed to the scene of the accident.
| A．available | B．enjoyable | C．suitable | D．acceptable |
Come and see me whenever ________.
| A．you are convenient | B．you will be convenient |
| C．it is convenient to you | D．it will be convenient to you |
________ by the growing interest in nature，more and more people enjoy outdoor sports.
| A．Influenced | B．Influencing | C．Having influenced | D．To be influenced |
___around the Water Cube, we were then taken to see the Bird’s Nest for the 2008 Olympic Games.
| A．Having shown | B．To be shown |
| C．Having been shown | D．To show |