22、It is not until recently ______ the scientists have found proof of there being water on Mars.

A. when                       B. that                          C. how                         D. what

21、______ our horizons of thinking, but it also saves us time and energy.

A. Not only does the Internet expand                 B. Not only expands the Internet

C. Not only the Internet expands                       D. Not only the Internet does expand

20、An excellent way to help memory is to connect information with pictures, which ______ as a memory-link method.

A. considers                 B. is considering           C. is considered            D. considered

19、 Air bags for cars were invented _____ lives. Without them more people would be injured in car accidents.

A. saving                   B. saved                    C. to save                   D. to have saved

18、Last year John earned _______ his brother did, who has a better position in a bigger company.

A. twice as many as                                                B. twice as much as

C. twice as more as                                                 D. twice much as

17、

16、 Can you lend me some money now?

Sorry, I have _____ left on me now. I must first go and withdraw some of my savings from the nearest ATM.

A. any                          B. some                        C. none                        D. much

15、He no longer lives on campus, for he _____ an apartment within the walking distance to the school.

A. will rent                   B. rented                      C. has rented                D. had rented

14、Tom and Jane used to walk _____ the bank after dinner when they were at university.

A. along                       B. in                            C. from                        D. across