Although medical science __________ control over several diseases,what worries us is that some of them are returning.
| A．achieved | B．has achieved | C．will achieve | D．had achieved |
28. —Has your sister finished her novel yet?
—I have no idea．She________it last week.
| A．wrote | B．has written | C．was writing | D．had written |
27．To shut your eyes to facts．as many of you do,_______foolish．
| A．is | B．are | C．are | D．Were |
26．There are all sorts of ways that employees can be successful_________obtaining the better office environment.
| A．in | B．On | C．about | D．For |
25. Thirty years ago this month，China's leaders launched an economic revolution.___________the door to free market reforms and foreign trade．
| A．to open | B．opened | C．opening | D．having opened |
24．According to a UN report，30 percent of the world population have no______to clean drinking water and health care.
| A．means | B．approach | C．channel | D．Access |