I. Read the passage and answer the questions Many cities have serious pollution problem. Motor vehicles, factories and other sources create so much air pollution that it may hang in the air like dirty frog. Air pollution threatens the health of the people who live in cities. City wastes cause water pollution when they are poured into waterways. These wastes kill fish and make some areas unfit for swimming. In addition, many large cities have difficulty disposing of their garbage. The amount of garbage grows each year, but places to put it are quickly filling up. Citizens, governments, industries, scientists, and business people must work together to gradually reduce pollution. 1.What makes the air polluted? => 2. How do city wastes influence to the life? => 3. Does the amount of garbage in the cities increases each year? => 4.What must people do to solve this problem? => 5.What should you do to reduce air pollution? =>