____all the inventions have in common is ____they have succeeded.

   A. What; what  B. That; that   C. what; that  D. That ; what

_________ you have seen both fighters，_________ will win？

A. Since； do you think who   B. As； who you think

C. When； whoever          D. Since； who do you think

Sarah hopes to become a friend of ______shares her interests.

A. anyone       B. whomever        C . whoever              D. no matter who

. I ______ pay Tom a visit, but I am not sure whether I will have time this Sunday.

  A. should                 B. might                       C. would                      D. could

 To be on the safe side, we should fill up the tank now, because we ______ run out of gas on the way.

  A. can                      B. would                      C. might                       D. should

---Will the Smiths go abroad this summer?             

---No, they finally decided  _______  .

              A. to              B. not going                  C. not to                D. not to be going

I used to __ to the south, so now, I am used to __ in a hot climate.

  A. go; live  B. going; living   C. go; living   D. going; live

________hard before, Tom is afraid of failing in the exam.

A. Having been worked        B. Not to have worked

C. Having never worked       D. Never have worked

I rushed there in a taxi only _______ the library_______.

　　A. finding; closed         B. finding; shut            C. to find; close     D. to find; closed

 Anything worth ______ is worthy of ______.

  A. doing, doing                                        B. doing, being done 

C. being done, to be done                          D. to be done, being done