Whether enough blood is donated could be a(an) ________ of life and death for the accident victims.
| A．concern | B．approach | C．affair | D．matter |
—I am going to America.
—how longyouthere?
| A．are; stayed | B．are; staying | C．have; stayed | D．did; stay |
Last Sunday, Mr. Green asked Lilyshe had written to her mother.
| A．that; yesterday | B．that; the day before |
| C．whether; yesterday | D．whether; the day before |
It’s notgood idea to drive for four hours withoutbreak.
| A．a; a | B．the; a | C．the; the | D．a; the |
The last thirty years _____ the greatest number of laws stopping our rights and progress,until today we have reached a stage ____ we have almost no rights at all.
| A．saw;which | B．have seen;that | C．saw;where | D．have seen;where |
As the sea ice melts sooner each swimmer,polar bears are forced to come ashore earlier and face food shortages _____ they have stored enough fat to last them through the season.
| A．before | B．unless | C．since | D．until |