______ 2010 Shanghai World Expo is a perfect opportunity to get ______ panoramic (全景的) view of the whole world without traveling thousands of miles.
| A．/; the | B．The; the | C．The; a | D．/; a |
I don't think the experiment is ___ failure, because it has provided us with ___valuable experience for our future tests．
| A．不填; 不填 | B．不填; a | C．a; 不填 | D．a; a |
As is known to us all, under no circumstances______ temporary economic development at the expense of the environment and resources.
| A．should we seek | B．we should seek |
| C．we had sought | D．had we sought |
We don’t care if a hunting dog smells _____, but we really don’t want him to smell ____.
| A．well, well | B．bad, bad | C．well, badly | D．badly, bad |
The present question is ____ many students consider it impossible ____ is really possible if effort is made.
| A．what; that | B．that ; that | C．that; what | D．what; what |
Some very common things such asto the sun for a long time will do harm to people's skin and even cause skin cancer
| A．exposing | B．being exposed | C．having exposed | D．exposed |