The science of computer, _____rapid progress has been made in recent years, is the most important of all science.
| A．to which | B．in which | C．of which | D．from which |
Had they known what was coming next, they ___________ second thoughts.
| A．may have | B．could have | C．must have had | D．might have had |
I don’t know how it ___________ that our car was bumped from behind.
| A．let out | B．gave out | C．got about | D．came about |
—How do you like your trip to Hainan?
—________,I enjoyed it very much，although the weather was hot sometimes.
| A．In addition | B．On the whole |
| C．In other words | D．On the other hand |
-----Why didn’t you ring me up?
----- Sorry, I forgot your phone number. Otherwise, I _____ long before.
| A．had rung you up | B．must run you up |
| C．would have rung you up | D．would ring you up |
My chest _____ when I take a deep breath, doctor.
| A．hurts | B．wounds | C．harms | D．injure |