The old lady’s hand shook frequently. She explained to her doctor _______this shaking had began half a year before, and ______, only because of this, she had to give up her job.
| A．when; how | B．how; when | C．how; how | D．why; why |
Not until he failed in the last examination _________ he should have spent more time on study.
| A．did he realize | B．he realized | C．did he not realize | D．he didn’t realize |
As a saying goes, the wise man knows he knows nothing, _________ the fool thinks he knows all.
| A．when | B．while | C．as | D．though |
We should show _________ concern for Mr. Smith, _________ eighty-year-old man near our home because now he has nobody to depend on.
| A．/; a | B．the; a | C．/; an | D．the; an |
Despite many worries before finishing the task, everything _________ well.
| A．turned out | B．put out | C．gave out | D．broke out |
According to the traffic rules, you _________ wear the safe belt while you are driving.
| A．can | B．need | C．may | D．shall |