—John, how did your English exam go?
— I thought I _____ , but in fact I came in the top 10% in the class.
| A．should have failed | B．might have failed |
| C．couldn’t have failed | D．mustn’t have failed |
Over the past decades, sea ice in the Arctic as a result of global warming.
| A．had decreased | B．decreased | C．has been decreasing | D．is decreasing |
—You speak very good French!
—Thanks. I __________ French in Sichuan University for four years.
| A．studied | B．study | C．was studying | D．had studied |
—Why don’t we choose that road to save time?
—The bridge to it __________.
| A．has repaired | B．is repaired |
| C．is being repaired | D．will be repaired |
The number of foreign students attending Chinese universities ________ rising steadily since1990.
| A．is | B．are | C．has been | D．have been |
-Why does the Lake smell terrible?
-Because large quantities of water .
| A．have polluted | B．is being polluted | C．has been polluted | D．have been polluted |