The earth is       years old.

A. four thousands six hundreds                                      B. four thousand six hundred

C. four thousand and six hundred million                     D. four thousand six hundred millions

They have made so great progress      .

                A. three years ago                                             B. for three years

                C. in the past three years                                D. before three years

— Has Li Hong gone to the library?

                  — Pardon?

                  — I asked       the library.

                  A. if Li Hong had gone to                                B. if had Li Hong gone to

                  C. Li Hong had gone to                                   D. has Li Hong gone to

— Oh, Miss Wei. Your skirt looks nice. Is it new?

                  — No, I       it since three years ago.

                  A. had                          B. bought                      C. have had                      D. have bought

— Must they clean and tidy the classroom now?

                  — No, they      . It       after school in the afternoon.

                  A. mustn’t; must clean                                   B. needn’t; must clean

                  C. mustn’t; need be cleaned                         D. don’t have to; can be cleaned

— It’s one o’clock now. I must go.

                  — It’s raining outside. Don’t leave       it stops.

                  A. when                      B. since                         C. while                             D. until

     your help, we can finish the task in time.

                  A. Thanks to              B. Thanks for               C. Because                       D. Thank

We should plant more trees on       sides of the street.

                  A. either                     B. both                          C. all                                   D. each

The world’s population was about 6.5 billion in 2008. ___46___ three billion people ___47___ Asia now. That’s about half of the world’s population.

China has the ___48___ population in the world, and about one fifth of the people in the world live in China. ___49___ the large population, there is ___50___ living space for each family. And it’s difficult for lots of people to find jobs. A large population also causes many ___51___ for ___52___ nation. For example, we are short ___53___ energy and water. Most cities are more ___54___ than before, and the traffic is much ___55___. The large population ___56___ a serious problem.

So far, our government has taken many measures to control the population. One is know ___57___ the one-child policy. It has worked ___58___ in controlling China’s population. Thanks to the policy, China is developing ___59___ and people’s living conditions are improving rapidly. However, the population problem is ___60___ serious in China. We still have a long way to go.

1.A. About         B. More       C. Over       D. Less

2.A. lived in        B. live in      C. lives in     D. live

3.A. largest         B. biggest     C. biggest      D. most

4.A. As            B. Because    C. For         D. Because of

5.A. more          B. less        C. little       D. fewer

6.A. difficulty       B. difficult    C. difficulty    D. difference

7.A. the all         B. all         C. the whole    D. whole

8.A. for            B. of         C. in          D. to

9.A. crowd         B. crowds     C. crowding    D. crowded

10.A. busy         B. heavy       C. heavily      D. heavier

11.A. become       B. becomes    C. became     D. has became

12.A. for          B. at          C. as          D. in

13.A. well         B. good        C. hard        D. hardly

14.A. quick        B. quickly      C. rapid       D. fast

15.A. ever         B. never        C. ready      D. still

About _____ of the world population is Chinese.

A. one third    B. one fourth    C. one fifth    D. one sixth