With so much work _________, they feel worried all the time.
| A．doing | B．to do | C．done | D．having done |
．He’s unlucky, and he’s always suffering _____ luck one after another．
| A．a sick | B．an ill | C．sick | D．ill |
．A computer is so useful a machine ________ we can use everywhere．
| A．that | B．whic h |
C．as | D．what |
He ________ the window of our classroom yesterday because he didn’t come to school．
| A．mustn’t have broken | B．mightn’t have broken |
| C．shouldn’t have broken | D．couldn’t have broken |
Mary had promised to give me a ticket for tomorrow．She failed, ____．
| A．either | B．though | C．but | D．too |
Mom promised to buy me a nice gift for my birthday , _____ beyond my imagination．
| A．which | B．that | C．something | D．the one |