1、 人教选修 6 Unit4 Global Warming GrammarTeaching materialNSEFC Book 6 Unit 4Teaching aimsEnable the students to master the usage of the form it is/was. that. Teaching important pointsHow to enable the students to know the structure and the usage of the form it is/was. thatTeaching difficult pointsHow to
2、 help the students to master the usage of the form it is/was. thatTeaching aidstape recorder, slidesTeaching proceduresStep1 RevisionT: First lets check answers. (slide show)Discovering useful words and expressions. (P28)1. Charles Keeling collected _on the carbon dioxide content in the atmosphere o
3、ver 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 wont _ of it for centuries.3. If the amount of greenhouse gases continues to _ we could be facing a global _.4. Many scientists believe that glob
4、al warming has _ through the burning of fossil fuels. They do not think that ignoring the issue is worth the _.5. _ describes weather conditions over a period of years in a particular place.6. The _ of a rising sea level would be widespread flooding.7. The use of energy in Susannas country is low _
5、the use of energy in the USA.8. The warming of the earth is a _ that causes great concern.9. The _ shows temperature changes during the 20th century.10. One hectare of forest can absorb 23 tons of carbon dioxide _ year.Keys： 1.data kept on 2. quantities; run out 3. build up; catastrophe4. come about
6、; risk 5. Climate 6. consequence pared to 8.phenomenon9. graph 10. perAnswer keys for Ex.2 on Page 28:The first graph shows the global _ between _ and _The temperature _ and decreased over this period but on the whole it _ by around _ and its highest in 2000. There was a steady _ in the temperature
7、during the twenty years after 1980. We can see from the graph that the earth has become _ since early last century.The second graph shows the amount of _in the atmosphere from _ to _ .The carbon dioxide _ steadily over this forty-year period. It went up from 315 to 370 parts _million.Keys：Temperatur
8、e；1860；2000；increased；rose ；1910 ；increase/rise；warmercarbon dioxide；1957；1997；increase/ went up；perStep2 Grammar强调句结构常考的强调句结构是it 引导的句子。一、It is (was) 被强调部分+ that (who) + 句子其他部分。此结构强调的成分仅限于主语，宾语和状语。It is from the sun that we get light and heat.It was not until I had read your letter that I understood
9、 the true state of affairs.Karl bought Marva a bicycle on her birthday卡尔在玛瓦生日那天给她买了一辆自行车。 It was Karl thatwho bought Marva a bicycle on her birthday（强调主语） It was Marva for whom Karl bought a bicycle on her birthday（强调间接宾语） It was a bicycle that Karl bought Marva on her birthday（强调直接宾语）注意区别强调句中的thatw
10、ho分句与定语从句： It was the student thatwho asked the silly question是一个学生问了这么一个愚蠢的问题。（分裂句） He was the student who asked the silly question他就是问了这么一个愚蠢问题的学生。（划线部分是定语从句） 二、not . until . 的强调形式: It is not until + 被强调部分 + that . “直到才”， 主要用于强调时间状语的强调句型。 We did not begin studying French until we entered universit
11、y我们进了大学才开始学法语。 要强调until we entered university，就成了： It was not until we entered university that we began studying French _ the 18th century that man realized that the whole of the brain was involved in the workings of the mind A. During B. In C. It was until D. It was not untilD对。直到十八世纪，人们才意识到：心理活动与整
12、个大脑有关。三、强调句的疑问句句型1.强调句的一般疑问句句型:Is / Was +it +所强调的部分+that / who/ whom +其它?2.强调句的特殊疑问句句型:特殊疑问词 + is/was it that / who/ whom+其它 ?Why is it that you hate winter？你究竟为什么不喜欢冬天？ How was it that you missed such a wonderful lecture？你怎么会错过这么精彩的报告？ When was it that they went abroad？他们什么时候出国的？ 四、判断强调句的方法判断是否是强调句
13、是，可把 It is / was that 去掉，剩余部分在不增减任何词的情况下还是一个完整的句子，那么这种句子是强调句。It was in the street that I met her father. In the street I met her father. It was because she was ill that they didnt ask her to do the job.Because she was ill, they didnt ask her to do the job.Step 3 Exercises一、根据划线部分把下列句子变成强调句。1. Peter
14、lent us the money.2. They want money.3. All this happened on Monday.4. I didnt hear form her until last summer.5.Why does everyone think I am narrow-minded？ Keys：1. It was Peter who lent us the money.2. It is money that they want.3. It was on Monday that all this happened.4. It was not until last su
15、mmer that I heard from her.5.Why is it that everyone thinks I am narrow-minded？二、Multiple choices1. It was in this village _ I was brought up.A. where B. that C. on which D. which2. Is it the factory_ this type of cars are produced?A. which B. where C. that D. /3. It was _ the old worker came that w
16、e _ the experiment.A. until; didnt begin B. not until; beganC. until began D. not until; didnt begin 4. It was in the lab _was taken charge of by Mr. Harris _they did the experiment.A. which，that B. that，which C. that， whom D. which，where5. It was _he did _frightened me.A. what，that B. that，that C. what，what D. that，what6. _ on Monday night that all this happened?A. Is it B.? It is C. Was it D. It wasKeys： BBBAACStep4 Homework1. Finish exercises of discovering useful structures (P29) and using structures on P64.2. Preview Using Language.