________ is known to us, May 12, 2008 was the day _______ Wenchuan earthquake happened.
| A．Which; on which | B．It; when |
| C．As; which | D．As; when |
—Excuse me, sir. Could you help me?
—Sure?
| A．What is that | B．What is it | C．What help | D．What do you want |
Shopping on line willtake the place of shopping in stores, won’t it?
| A．commonly | B．especially | C．finall y |
D．regularly |
Had I mastered the statistic technique, a large amount of time and, energy.
| A．was avid | B．had been saved | C．will be save d |
D．would have been saved |
It is meetingside effect the new medicine will bring about, although the experts have tried it on about 2,000 patients.
| A．that | B．what | C．whether | D．which |
Now methods need to beto use the existing water resources, for example, turning sea water into fresh water.
| A．developed | B．assumed | C．abandoned | D．purchased |