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You have heard a lot about ozone layer on TV and radio. The ozone layer has a hole in it. There are high ozone levels in the air. Do you know ozone is good or bad? The good ozone is found miles above the earth. That is an ozone layer. But the ozone layer is becoming thinner. It is being destroyed by chemicals from refrigerators, air conditioners and farms. As the ozone layer is destroyed, more harmful UV rays (紫外線) are reaching the Earth's surface. There are more cases of skin cancer among humans. Production of corn and other crops (農(nóng)作物) is reducing. Plants in the oceans are being destroyed. Food supplies could be reduced.
There is good news, however. The ozone layer is thinning at a slower speed. Many of the chemicals that destroy ozone have been stopped. Scientists believe that someday the hole in the ozone layer will be repaired (修理).
The bad ozone is found near the ground. It is a form of air pollution. High levels of bad ozone can cause healthy problems. Anyone, even healthy people, spends a lot of time outside in summer, and they can be affected. Bad ozone comes from cars and factories.
As with other forms of air pollution, steps can be taken to reduce ozone. Save energy in your home by turning off electric equipment. Reduce ozone from cars by carpooling (拼車), bicycling, or taking public transportation.
閱讀短文，并根據(jù)短文內(nèi)容回答所提問題。
1. How many kinds of ozone are there?
2. What do UV rays cause people on the earth?
3. Why is the ozone layer thinning at a slower speed now?
4. Where can people find bad ozone?
5. How can we reduce the bad ozone in our life?
