The old woman at the street corner must be lost．She is looking around ________ for someone to help her．

A．socially

B．accidentally

C．extremely

D．desperately

Polar bears live mostly on ________ sea ice, which they use as ________ platform for hunting seals．

A．a; a

B．a; the

C．不填；a

D．the；不填

－Would you like to take ________ sugar in your tea?

－No, thanks．I used to, but now I’m on ________ diet．

A．the; a

B．×; ×

C．×; a

D．the; the

________ the exam will disappoint your parents．

A．You failing

B．Your failing

C．You fail

D．You to fail

E-mail, as well as telephones, ________ an important part in our daily life．

A．is playing

B．have played

C．are playing

D．play

The light is on in his room．Tom ________ his homework．

A．must do

B．can do

C．must be doing

D．may have done

He realized that she was crying ________ what he had said．

A．because of

B．because

C．as if

D．so that

As the boy was weak in health, his doctor ________ him to take more exercise．

A．hoped

B．suggested

C．thought

D．advised

________ your spirits．Try again and you’ll succeed．

A．Catch up

B．Keep on

C．Keep fit

D．Keep up

The Olympic Games ________ 776 BC are held every four years．

A．dates back to

B．dated from

C．date from

D．dating back to