We walked a couple of blocks, looking in _______ for a taxi. How disappointed we were!
| A．place | B．order | C．return | D．vain |
Come and see me whenever _____.
| A．you are convenient | B．you will be convenient |
| C．it is convenient for you | D．it will be convenient for you |
They covered the body of the little hero with a flag, ____his face to the public.
A to expose B exposing C exposed D expose
To our surprise, the man looking very rude____ his son very carefully.
| A．take care | B．look after | C．attended | D．All of the above |
The theory he ____ about black hole isn’t understood by most of people.
A .put up B put down C put off D put forward
It will be many years ______ the doctors and medical scientists can find _____ for cancer.
| A．since; cures | B．when; treatments |
| C．before; cures | D．until; treaments |