21天搞定英語四六級閱讀理解 點擊加入

　　2022年大學英語四級作文預(yù)測：空氣污染

　　Hotter or Colder

　　It was once thought that air pollution affected only the area immediately around large cities with factories and/or heavy automobile traffic.Today, we know that although these are the areas with the worst air pollution,the problem is literally worldwide.On several occasions over the past decade,a heavy cloud of air pollution has covered the entire eastern half of the United States and led to health warnings even in rural areas away from any major concentration of manufacturing and automobile traffic.

　　In fact, the climate of the entire earth may be affected by air pollution.Some scientists feel that the increasing concentration of carbon dioxide in the air resulting from the burning of fossil fuels (coal and oil) is creating a “greenhouse effect” —holding in heat reflected from the earth and raising the world’s average temperature.

　　If this view is correct and the world’s temperature is raised only a few degrees,much of the polar ice cap will melt and cities such as New York, Boston, Miami,and New Orleans will be under water.Another view, less widely held,is that increasing particulate matter in the atmosphere is blocking sunlight and lowering the earth’s temperature —a result that would be equally disastrous.A drop of just a few degrees could create something close to new ice age and would make agriculture difficult or impossible in many of our top farming areas.

　　At present we do not know for sure that either of these conditions will happen (though one recent government report prepared by experts in the field concluded that the greenhouse effect is very likely).Perhaps, if we are very lucky,the two tendencies will offset each other and the world’s temperature will stay about the same as it is now.

　　點擊下方↓↓鏈接領(lǐng)取[四六級]真題\模擬題等資料>>>

掃描二維碼下載題庫幫助四六級學習

加入四六級學習打卡營

獲取四六級歷年真題

四六級考試手機做題

獲取四六級模擬試題

萬題庫下載|微信搜索”萬題庫英語四六級考試“

　　相關(guān)推薦：

　　2022年英語四六級考試時間 | 英語四級作文 | 六級作文

　　歷年大學英語四級考試真題聽力(含MP3)匯總

　　歷年大學英語四級真題及答案|解析|估分|下載

　　歷年大學英語六級真題及答案|解析|估分|下載

　　歷年大學英語六級考試聽力下載(原文+MP3)匯總

　　2022年大學英語四級考試真題 | 英語六級考試真題答案