He________have completed his work; otherwise, he wouldn't be enjoying himself by the seaside.
| A．should |
| B．must |
| C．wouldn't |
| D．can't |
Not only________ vital for reducing fever and helping stop pain, but there are also other things that aspirin can help with.
| A． aspirin has proved | B．did aspirin prove |
| C．has aspirin proved | D．aspirin proved |
They kept trying, and their efforts finally _____. They got enough money to _____ their debt.
| A．are paid off; pay back | B．paid off; pay off |
| C．are paid for; pay back | D．paid back; pay off |
He is disappointed. He appears ____ what has happened to his competition.
| A．knowing | B．to know |
| C．having known | D．to have known |
I was watching the news on TV ________ the power went off.
| A．when | B．as | C．while | D．until |
It was not until I failed in the test ______ I realized I had wasted too much time instead of preparing for it fully.
| A．did | B．before | C．that | D．where |