—Why was Professor Zhang unhappy recently？

       —Because the theory he insisted on _________ wrong.

       A. proved         B. proving  C. being proved     D. was proved

. — Why was Professor Johnson unhappy those days?

— The only reason was ________the theory he stick to ____ wrong.

—Why was Professor Liu thundering in the classroom yesterday?

   —A student’s interrupting his speech ________the burst of his anger.

   A．set up           B．set out 

   C．set about         D．set off

 — Why was Professor Johnson unhappy those days?

— Can’t you see it clearly? The only reason was that the theory he stuck to________ wrong.

A. proving                               B. being proved    

C. proved                            D. was proved

 — Why was Professor Johnson unhappy those days?

— Can’t you see it clearly? The only reason was that the theory he stuck to________ wrong.

A. proving                               B. being proved    

C. proved                            D. was proved