II. Complete the sentences by filling in each blank with a suitable preposition 11. It is believed that many of the plants and animals can be used ……….medicines against canner. 12. There is a large variety…………………plants and animals in the national parks 13. We learn about how one species is dependent……………another for survival 14. The scientists are searching……………..answers how to protect natural environment 15. Some of the rare species are ……………..danger of being extinct 16. Hydroelectric dams hold back needed water and provide power ………………..homes and industries 17. The government have take some measures to clean ……………the polluted rivers and seas 18. Without plants, most of the water would run ………………as soon as it falls 19. Can you tell me how important water is ………………our life? 20. What should we do ……………..the future of our planet? III. Give the right tense of each verb in brackets 21. Please wait here until I (call)………………..your name. 22. Hurry up! Everyone (wait)……………..for you. 23. While I (drive)………………..on the high way, I (see)…………….a terrible accident. 24. He (study)……………….the effects of radiation when he suddenly (die)………………… 25. We were disappointed that most of the guests (leave)…………..when we (arrive)………. at the party. 26. When the police (come)……………., the thieves (go)………..away for 10 minutes before. 27. The light (go)………….…out while we (have)……………….dinner. 28. We (not see)……………….each other since we (meet)…………….at Lan’s party. 29. I am sure that Bill (get)………………the job because he has a lot of experience. 30. Jane (write)………………to her husband twice a week. IV. GRAMMAR a. Use the right form of passive or active of verbs 31. A new bridge (build) …………..…..across the river last year. 32. He (photograph)………………………….by many journalists now. 33. You (finish)………………….your homework yet? 34. Sarah’s mother (make)………………..a big cake for her birthday tomorrow. 35. They (translate)…………………. the novel into many different languages so far. 36. What you (do)………………at 7 pm last night? 37. The meeting (change)………………….. from Monday to Friday next week. 38. What language (speak)……………………. in Brazil? 39. People (speak)………………. English in many parts of the world. 40. When I got to the cinema, the film (show)…………….for twenty minutes. b. Change into passive voice 41. People have spent a lot of money on advertising → ……………………………………………………………………………………… 42. They are building a new bridge across the river → …………………………………………………………………………………… 43. People speak English all over the world → ………………………………………………………………………………… 44. They have provided the victims with food and clothing → ………………………………………………………………………………………… 45. Is she making a big cake for the party? → …………………………………………………………………………………………….. 46. Karl Benz built the first motor car in 1885 → ……………………………………………………………………………………………. 47. Martha was delivering the documents to the department → …………………………………………………………………………………………….. 48. They are painting the kitchen now → …………………………………………………………………………………… 49. Have you finished your homework yet? → ……………………………………………………………………………………………... 50. They have just built a new primary school in my village → ……………………………………………………………………………………………...