Please keep us ____ of any change of address as soon as possible.

A. informing      B. informed            C. being informed     D. to inform 

By the end of 2008, about half a million people had flooded into the city, _____ up around 10 percent of its total population.

A. make         B. made                     C. making          D. to be made  

______ untidily and speaking in a strange way, father must have appeared to the people present to be a silly old man.

A. Dressing  B. Dressed  C. Being dressed  D. To be dressed

______ his telephone number or e-mail address, she had some difficulty ____ in touch with John.

A. Not knowing; getting    B. Not having known; to get  

C Knowing not; to get      D. Having not known; getting

Silver is the best conductor of electricity, copper _______ it closely.

A. followed     B. following      C.  to follow    D. follows

 Seeing everything remained ___ as it had been two hours before, the boss couldn’t help shouting at the secretary.

A. to be done   B. being done   C. having undone   D. undone

The _____ boy never dares to see the ____ film again.

A. frightened; frightening    B. frightening; frightened

C. frightened; frightened      D. frightening; frightening

When first     in China, Prison Break made Chinese viewers crazy about it．

A．screening                  B．to screen      C．screen   D．screened

With all his attention _______ on the computer game, the boy even didn't notice his mother came in.

A. was fixing    B. was fixed     C. fixing     D. fixed

The wealthy merchant went into the house, with two bodyguards ____ him.

 A. to follow  B. following  C. follow  D. followed