课时跟踪练(一) Welcome to the unit & Reading.阅读理解APeople and the sources of air pollution are found in the same places. This means that cities with large populations have the biggest problem of dirty air. Air pollution is caused by many different things. A major source of air pollution is the gas fumes (烟雾) from cars. Statistics show that 93 percent of all auto trips are within cities. Another major source of dirty is the burning of coal and oil for energy. This energy is needed to make electricity. Of course, much more electricity is used in the city than in the countryside.On the average, we throw away more trash and garbage than the year before. The burning of garbage contributes to air pollution. Many major industries are also responsible for the dirty air in the around cities. The fumes from iron, steel, chemical, and petroleum (石油) production add particles (微粒) to the air.The effects of air pollution range from loss of clear vision, mild headaches to death. Wherever coal and oil are used for fuel, fumes may kill trees and plants and cause metal to corrode (腐蚀). In some larger cities, these fumes endanger the life of human beings by contributing to lung diseases and causing early deaths.语篇解读：本文主要介绍了城市空气污染的原因与后果，旨在呼吁人们停止继续污染空气。1The key point of the passage is that .Athe cause of air pollution is peopleBthe causes and the effects of air pollution are both found in citiesCthe effects of air pollution range from headaches to deathsDair pollution is caused by dirty air解析：选B主旨大意题。根据各段首句，特别是第一段的首句可知，本文主要讲的是城市里的空气污染原因与后果。2What is the purpose of this passage?ATo persuade people to stop polluting the air. BTo tell the causes of air pollution.CTo tell why cities have larger populations. DTo describe why cities are bad places to live.解析：选A写作意图题。空气污染严重危害人的健康，所以本文的目的是呼吁人们停止污染空气。3Why is air pollution heavier in the city than in the countryside?ABecause there are more people in city.BBecause the air in the city is thinner.CBecause there are more cars in the city.DBecause there are more air pollution sources in the city.解析：选D细节理解题。根据第一段第二、三两句可知，城市里有更多的空气污染源。4In larger cities, the fumes from coal and oil may result in .Aheart diseasesBserious headachesClung diseases Dloss of clear vision解析：选C细节理解题。根据文章最后一句可知选C。B There is an old Chinese proverb that states “One generation plants the trees; another gets the shade”， and this is how it should be with mothers and daughters. The relationship between a mother and daughter is sometimes confusing. If close, the relationship can be similar to friendship. However, the mother and daughter relationship has unique characteristics that distinguish it from a friendship. These characteristics include the hierarchy (等级) and unconditional love，which preclude mothers and daughters from being best friends.Marina, 27 years old, says, “I love spending time with my mom, but I wouldnt consider her my best friend. Best friends dont pay for your wedding. Best friends dont remind you how they carried you in their body and gave you life！Best friends dont tell you how wise they are because they have been alive at least 20 years longer than you.” This doesnt mean that the mother and daughter relationship cant be very close and satisfying.While some adult relationships are still troubled, many find them to be extremely rewarding. This generation of mothers and adult daughters has a lot in common, which increases the likelihood of shared companionship. Mothers and daughters have always shared the common experience of being homemakers, responsible for maintaining and passing on family values and traditions. Today contemporary mothers and daughters also share the experience of the workforce and technology, which may bring them even closer together.Best friends may or may not continue to be best friends, but for better or worse, the mother and daughter relationship is permanent, even if they arent speaking for some unfortunate reason. The mother and daughter relationship is still closer than any other. There is not an equal relationship. Daughters should not feel responsible for their mothers emotional wellbeing. It isnt that they dont care deeply about their mothers. Its just that they shouldnt be burdened with their mothers wellbeing.The mother and daughter relationship is a relationship that is not replaceable by any other. Mothers never stop being mothers, which includes frequently wanting to protect their daughters and often feeling responsible for their happiness. Mother always “trumps” friends.语篇解读：本文对比了母女之间的友谊和好朋友之间的友谊，主要是为了说明母女之间的友谊更持久。5The underlined word “preclude” in Paragraph 1 probably means “ ”Adiffer BpreventCbenefit Dchange解析：选B词义猜测题。根据第二段“Best friends dont pay for your wedding .Best friends dont tell you how wise they are .”可推断，这里指母女之间不能成为最好的朋友，preclude意为“阻止”，故答案为B。 6Why do many mothers and adult daughters kee