9. A. but B. and C. however D. because

10. A. same B. useless C. many D. valuable

11. A. experience B. height C. age D. size

12. A. matches B. football C. education D. pupils

13. A. where B. there C. their D. because

14. A. learning B. education C. a textbook D. physical education

15. A. school B. lab C. library D. classroom

16. A. quickest B. cheapest C. best D. modernist

17. A. especially B. usually C. seldom D. hardly

18. A. fight B. struggle C. work D. study

19. A. teachers B. pupils C. players D. team

20. A. eyesight B. head C. foot D. body

阅读下面材料, 在空白处填入适当的内容（1个单词）或括号内单词的正确形式。

　　The way we cook is important. In many countries, the two choices are 1. . (nature) gas or electric powered stoves.

　　The World Health Organization warns that millions of people 2. (suffer) from indoor air pollution at present time, which results from the use of 3. (danger) fuels and cookstoves in the home.

　　WHO officials say nearly three billion people are 4. (able) to use clean fuels and technologies for cooking, heating and lighting. As a result, more than seven million people die from exposure to indoor or outdoor air pollution each year. Most of the deaths are in 5.______ (develop) countries, such as India, China and Latin American countries.

　　WHO officials say opening a window or door 6. (let) out the harmful air will not correct the situation 7 will only pollute the outdoors.

　　Nigel Bruce, 8 is a professor of Public Health at the University of Liverpool, says researchers are developing good cookstoves and other equipment to burn fuels 9 a more efficient way.

　　But, this is just a start. It is urging developing countries to use 10 (clean) fuels and increase access to cleaner and more modern cooking and heating appliances (用具) .