Loulan is believed __________ over by sandstorms gradually from AD200 to AD400.
| A．to cover | B．to be covered |
| C．to have covered | D．to have been covered |
—Do you think the weather will be all right this summer?
—No, _____ we are lucky. The newspaper says it'll be very hot anyway.
| A．if | B．though | C．unless | D．as |
— Did you have a wonderful time at the ball last night?
— __________! I’ve never had a more wonderful time all my life.
| A．You bet | B．No problem | C．Don’t mention it | D．Got it |
You may ______ it that Jennifer will come and help us if we are in trouble.
| A．base on | B．rely on | C．carry on | D．hold on |
Not until he left his home ______ to know how important the family was for him.
| A．had he begun | B．did he begin | C．he began | D．he had begun |
Britain, ______________many other industrialized countries, ______ experienced major changes over the past 100 years.
| A．together with; have | B．as well as; have |
| C．in common with; has | D．instead of ; has |