人教版高二英语Unit4LearningaboutLanguage.ppt

Unit 4 Global warming Learning about Language 1. Review some important language points. 2. Check up the answers of the exercises on P28. 3. Learn a new Grammar—It的用法及强调结构 Go over the new words and phrases in the previous sections. Then complete each sentence with one of those new words or phrases. Discovering useful words and expressions 1. Charles Keeling collected ______on the carbon dioxide content in the atmosphere over a forty-year period. He found that the amount of carbon dioxide _______ increasing during that time. 2. Although we are burning coal in huge _________ every year, we won’t ________ of it for centuries. 3. If the amount of greenhouse gases continues to _______, we could be facing a global __________ . data kept on quantities run out build up catastrophe 4. Many scientists believe that global warming has __________ through the burning of fossil fuels. come about 5. The _____________ of a rising sea level would be widespread flooding. 6. On the whole the warming of the earth is a ____________ that causes great concern. 7. The __________ shows temperature changes during the 20th century. 8. One hectare of forest can absorb 23 tons of carbon dioxide ____ year. consequence phenomenon graph per 9. The washing machine uses too much energy, but _________ we buy a more economical one, it would still use too much water. 10. The car accident on the main road yesterday ___________ one driver’s death. even if resulted in It的用法及强调结构 1. 代词 （1）用作人称代词, 代替前文提到的事物。 My watch is missing. I can’t find (it) anywhere． Her father has gone abroad. Have you heard about (it)? （2）代替指示代词this, that。 What’s this? (It’s) a computer． Whose pen is that? (It’s) mine． （3）表示时间、天气、距离、季节、度量等。 It’s time for lunch. It’s getting warmer and warmer． It’s forty years since my hometown was liberated． It’s summer now． How far is it from here to the airport？ It’s about twenty minutes’ walk from here to the bus stop． 2. 引导词 （1）作形式主语, 代替由不定式,