Unit4_Global_warming课件27(新人教版选修6）.ppt

人教课标版 高二选修6 Unit 4;Discovering useful words and expressions;Discovering useful words and expressions (P28);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 __________.;4. Many scientists believe that global warming has __________ through the burning of fossil fuels. ;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.;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.;由it引导的强调句结构： It is (was)+被强调部分+that (who) + 句子其他部分 注意：此结构强调的成分仅限于主语，宾语和状语。;如： 原句：My father did the experiment in the lab yesterday evening． 强调主语：It was my father who/that did the experiment in the lab yesterday evening．;强调宾语：It was the experiment that my father did in the lab yesterday evening． 强调时间：It was yesterday evening that my father did the experiment in the lab．;强调地点：It was in the lab that my father did the experiment yesterday evening． e.g. It was in that city that we met for the first time． It was not until he told me that I knew the truth．;典型例题分析： 1) It was last night ____ I saw the film Star Wars． A. who B. when C. that D. which;答案C 强调句的结构是：It + be + 强调部分 + that (who) +主谓句。强调句的连词只有两个，that和who。当强调的部分是人，且为句子的主语时，才用who，其余用that。;2) It is ten years ____ Miss Green returned to Canada． A. that B. when C. since D. as 答案C 考点是连词用法。本题易误选为A其实本句不是强调句。; 若是去掉It be…that