13. Air and water _______________can make people fall ill. (pollute)
14. We should make our world ___________________. (pollute)
15. You may face a ________________or termination of benefits. (reduce)
16. Without practice, hopes will be _________________to zero. (reduction)
17. She is a very helpful and ____________ woman. (energy)
18. _______________, the student couldn’t answer the examiner’s question exactly. (disappoint)
19. Every citizen may claim the ________________of the law. (protect)
20. Trees should be well _____________from the cold during winter. (protect)
21. The drugs work well at first but gradually lose their ______________. (effective)
22. The company must reduce costs to compete _________________. (effect)
23. Food, clothing and shelter are all basic ________________of life. (necessary)
24. In writing this report, I have omitted all ___________________details. (need)
25. Does that machine work ______________? (effect)