The invention of_________ paper was a great contribution to________human civilization.
| A．a;a | B．the;the | C．/;/ | D．the;/ |
---When did you learn the news that Obama made a trip to Canada as President?
--- _________ was on my return.
| A．That | B．It | C．There | D．This |
Joined by their friends, Troy and Gabriella staged a musical _______ their experiences, hopes and fears about the future.
| A．reflecting | B．reflected | C．being reflected | D．having reflected |
You _______ late for yesterday’s class meeting, as it was so important.
| A．couldn’t | B．shouldn’t be | C．mustn’t have been | D．oughtn’t to have been |
Why do we have to ________ Joan’s selfish behavior? She should learn to care for others.
| A．keep up with | B．catch up with | C．put up with | D．come up with |
By the end of last year, another new theme park _______ completed in that area.
| A．was being | B．would be | C．has been | D．had been |