课文语法填空 The Earth Is Becoming Warmer — But Does It Matter? During the 20th century the temperature of the earth rose about one degree Fahrenheit. That probably does not seem much to you or me, 1.________ it is a rapid increase when 2.________ (compare) to other natural changes. There is no doubt that the earth is becoming 3.________ (warm) and that it is human activity 4.________ has caused this global warming. All scientists subscribe 5.________ the view that the increase in the earth's temperature is due to the burning of fossil fuels like coal, natural gas and oil to produce energy. Some byproducts of this process are called “greenhouse”gases, 6.________ most important one of which is carbon dioxide. We know that the levels of carbon dioxide have increased greatly over the last 100 to 150 years. Charles Keeling found that between these years the carbon dioxide in the atmosphere went 7.________ from around 315 parts to around 370 parts per million. Greenhouse gases continue to build 8.________ in the atmosphere. Even though we start reducing the amount of carbon dioxide and other greenhouse 9.________ (gas), the climate is going to keep on 10.________ (warm) for decades or centuries.