— that made him unhappy?
—Well, failing in his English test.
| A．Where was it | B．What was it | C．How was it | D．Why was it |
Do ____ you think is right, ____ difficulties you may have.
| A．what; however | B．that; whatever |
| C．whatever; whoever | D．what; whatever |
—Why can't I smoke here?
—At no time__________ in the meeting-room
| A．is smoking permitted | B．smoking is permitted |
| C．smoking is it permitted | D．does smoking permit |
______ it is true that a student’s most important goal is to do well in his or her studies, it doesn’t need to be the only goal.
| A．When | B．As | C．While | D．Before |
He devoted most of his time to his research, believing his hard work would___sooner or later.
| A．put off | B．take off | C．come off | D．pay off |
China, a country with 145 million elderly people, will remain _______ ageing society during this century, according to _______ Chinese population experts.
| A．/; the | B．an; / | C．an; the | D．the; / |