Choose the letter A, B, C or D to complete the sentences with given words 6. Unless/ storm/ happen/ this evening/ we/ go/ camping. A. Unless the storm doesn’t happen this evening, we will go camping. B. Unless the storm happens this evening, we will not go camping. C. Unless that storm happens this evening, we will go camping. D. Unless the storm happened this evening, we will go camping. 7. If / we /not start/ work / cleaner sources / energy/ environment/ seriously polluted. A. If we don’t start work on cleaner sources of energy, our environment will seriously polluted B. If we don’t start working on cleaner sources of energy, our environment is seriously polluted. C. If we not start working on cleaner sources of energy, our environment will be seriously polluted. D. If we don’t start working on cleaner sources of energy, our environment will be seriously polluted. 8. If/ there/ be/ much/ exhaust fume/ air/ more/ people/ cope/ respiratory problem//. A. If there is too much exhaust fume in the air, more and more people will cope with respiratory problem. B. If there will be too much exhaust fume in the air, more and more people will cope with respiratory problem. C. If there are too much exhaust fume in the air, more and more people will cope with respiratory problem. D. If there was too much exhaust fume in the air, more and more people will cope with respiratory problem.