We haven't settled the problem of ________ it is necessary for him to study abroad.
| A.why | B.whether | 
| C.what | D.how | 
-Are you satisfied with her answer?
 -Not at all. It couldn’t have been _____.
| A.worse | B.so bad | C.better | D.the worse | 
. -What do you think of the book? 
 -Oh, excellent. It is worth _____ second time.
| A.to read a | B.to read the | C.reading a | D.being read the | 
The three college students did what they could _____ the two children, although they was in danger.
| A.rescue | B.rescued | C.to rescue | D.rescuing | 
-Have you got your test result? 
 -Not yet. The papers _____.
| A.are still being corrected | B.are not correcting | 
| C.have already been corrected | D.have not corrected | 
_______ a mobile phone can you ring _______ you want to talk with anywhere .
| A.Using; whoever | B.Only on; whomever | C.By; whomever | D.With; whoever w |