One of the most urgent environmental problems in the world today is the shortage of clean water.Having clean drinking water is a basic human right. However, acid rain, industrial pollution and garbage have made many sources of water undrinkable. Lakes, reservoirs and even entire seas have become vast pools of poison. Lake Baikal in Russia is one of the largest lakes in the world. It contains a rich variety of animals and plants, including 1, 300 rare species that do not exist anywhere else in the world. Yet, they are being destroyed by the massive volumes of industrial effluent which pour into the lake every day. Even though laws have been made, the government do not have the power to enforce them. Most industries simply ignore the regulations. The Mediterranean Sea occupies 1% of the world's water surface, but it is the dumping ground for 50% of all marine pollution. Almost 16 countries regularly throw industrial wastes a few miles off shore.        Water is free to everyone. A few years ago people thought that the supply of clean water in the world was limitless. Today, many water supplies have been ruined by pollution and sewage. Clean water is now scarce, and we are at last beginning to respect this precious source. We should do something now. 29. According to the writer, one environmental problem in the world today is ________ A. safe water shortage                                                 B. pools of poison C. industrial pollution                                                   D. population explosion 30. What is the serious problem of Lake Baikal in Russia? A. It has 1, 300 rare species that do not exist anywhere else in the world. B. It is one of the largest lakes that contains a variety of animals and plants. C. It is polluted by massive volumes of industrial wastes discharged into it. D. It is the only lake in Russia whose source of water is not drinkable. 31. What does the word "them" in the passage refer to? A. laws                               B. the government            C. animals                          D. plants 32. What is the message to the readers? A. We should take action to protect our water sources. B. We should take all water sources into account. C. We should limit the use of water sources. D. We should encourage people to use safe water. Mark letter A, B, C or D on your answer sheet to indicate the sentence that is closest in meaning to the original sentence in each of the following questions. 33. I eat a lot. I cannot keep fit. A. Due to eating a lot, I cannot keep fit.                     B. Although I eat a lot, I cannot keep fit. C. The more I eat, the less fit I become.                     D. I become fit not only because I eat a lot. 34. The doctor about whom I told you last week is working here. A. I told you about the doctor last week . He is working here B. I told you the doctor last week . He is working here. C. The doctor about that I told you last week is working here. D. The doctor whom I told you last week is working here. 35. “Would you like to go to the show with me?" Anna said to Bella. A. Anna reminded Bella to go to the show with her. B. Anna persuaded Bella to go to the show with her. C. Anna encouraged Bella to go to the show with her. D. Anna invited Bella to go to the show with her.