1、Unit8,. Objectives,. Suggested Teaching Plan,. Background Information,. Class Presentation,Preview,Preview,This is the last unit of Book Two. In the Listening and Speaking section, you will learn how to ask for and give reasons. In the Reading and Writing section, you will read three passages about
2、science and technology. Text A was written at the turn of the 21st century and the writer predicted the top five scientific developments of the coming century. Text B concerns issues of safety that must be guaranteed when the frontier of science and technology is being pushed back. Practical Reading
3、 is a form that people need to fill out upon arrival in the U.S.,prev.,. Objectives,After studying this unit, the students are expected to be able to,Obj.,master the basic language and skills necessary to ask for and give reasons;,1.,understand the main ideas of Texts A and B, and master the useful
4、sentence structures and words and expressions found in the exercises relevant to the texts;,2.,3.,know how to use V-ing phrases, V-ed phrases and To V phrases as adverbials;,4.,know how to write an email;,6.,understand paragraph development (5).,5.,read a form that people need to fill out upon arriv
5、al in the U.S.,. Suggested Teaching Plan,Suggested Time and Teaching Plan for Unit 8,Time,Contents,Plan,1) The Language for Asking For and Giving Reasons,Give a brief lead-in talk on the nature and uses of asking for and giving reasons;,A.,s.t.p.1,The teacher begins with the Preview to make sure tha
6、t the students have a general idea of what this unit is all about. After that, the teacher activates listening and Speaking exercises as follows:,2 periods,Preview,Listening and Speaking,B.,Present the necessary language by doing Exercise 1;,C.,Ask one student to read aloud the talk so students can
7、check their completed answers;,D.,Organize an activity for Ex. 2 that will reinforce the useful language students picked up in Ex. 1.,Time,Contents,Plan,s.t.p.1.2,2) The Practice of Asking For and Giving Reasons,Go through the new words in the first conversation in Ex. 3;,A.,B.,Have the students lis
8、ten to the conversation twice and fill in the blanks with the missing words;,C.,Ask them to answer the questions about the conversation;,D.,Tell them to look for the language used to asking for and giving reasons;,Time,Contents,Plan,s.t.p.2,Ask the students to role-play the conversation;,Have them l
9、isten to the second conversation twice and complete the short passage accordingly;,F.,E.,Suggest they discuss each of their completed answers in order to gain a better understanding of the conversation;,G.,Now, have them listen to the conversation again and complete the form as the speaker recounts
10、it;,H.,Afterwards, have them check their responses by acting out the conversation;,I.,Time,Contents,Plan,s.t.p.3,3) Listening Practice,Before ending, the teacher tells the students to do Ex. 5-10 as their assignment to review the functional and notional language picked up in the Listening and Speaki
11、ng section. The teacher also tells them that they should be prepared to answer the questions in Exercise 9 and give an oral presentation in class when they next meet.,Organize a unique classroom activity for Ex. 4 that will reinforce the useful language students picked up earlier in the unit.,J.,3 p
12、eriods,Review of the listening and speaking skills the students have learned,The teacher begins with a review of the functional and notional language the students picked up in the previous classes. The teacher asks several students to answer the questions in Ex. 9 of the Listening and Speaking secti
13、on, and invites a few to share with their classmates their opinions on the topic “It is more important to raise questions than to answer them.” Then, the teacher turns to the Reading and Writing section. (These activities should be completed in 15 minutes.),s.t.p.4,Time,Contents,Plan,1) Starter,Afte
14、r a brief explanation of the instructions, the teacher,A.,gives the students a few minutes to think about the questions in the starter;,s.t.p.5,Time,Contents,Plan,B.,asks some students to answer the questions.,2) Text A,A.,The teacher,lets the students answer the text-related questions, helps them i
15、dentify the main idea of each paragraph, and analyzes some difficult sentences and some language,Text A & text-related exercises,B.,guides the students through the exercises, focusing on certain items or leaving some exercises as the students homework according to the students different levels of En
16、glish (one period).,s.t.p.8,1 period,Grammar Review,1) Grammar Review,The teacher talks about the use of V-ing phrases, V-ed phrases and To V-phrases as adverbials, and at the same time asks the students to do the grammar exercises in class.,Time,Contents,Plan,points while discussing the whole text
17、with the students (one and a half periods);,s.t.p.9,Practical Writing,2) Practical Writing,The teacher explains to the students how to write an email by doing Ex.12 of Practical Writing, and then requires the students to do Ex.13 and Ex.14 after class.,Time,Contents,Plan,s.t.p.10,2 periods,Text B, &
18、 Text-related exercises,1) Text B,While discussing the text with the students, the teacher calls on them to pay attention to the structure of the paragraphs of the text, introducing briefly the concept of the topic sentence. Ex.16 and Ex.17 can be done either in or after class.,2) Practical Reading,
19、This part should either be read by the students themselves as their homework or done in class.,Time,Contents,Plan,Practical Reading,s.t.p.11,Basic Reading Skills,3) Basic Reading Skills,The teacher explains to the students paragraph development (5), and asks them to do the exercises in Basic Reading
20、 Skills.,Time,Contents,Plan,. Background Information,James Trefil,Original Text of “The Top 5 Scientific Breakthroughs of the 21st Century”,BI,Modern Science (20th century),Three Mile Island,The Chernobyl Accident,Radiation sickness,Soviet Union and Russia,BI-JT,James Trefil,As an award-winning auth
21、or and physicist, James Trefil has written more than 25 books on a range of science topics. Hes a contributor to National Public Radio and Smithsonian Magazine, and a physics professor at Virginias George Mason University, U.S.A.,Original Text of “The Top 5 Scientific Breakthroughs of the 21st Centu
22、ry”,The 20th century produced scientific and technological change at a dizzying pace-greater than in any other century in history. But the 21st century, the dawn of the new millennium, may well see even more dramatic change driven by advances in science and technology. On these pages are my predicti
23、ons for the top scientific developments well see in the next 100 years, in the order I think theyll happen.,BI-OT1,(其中提及了作者进行预测的根据),James Trefil,BI-OT2,1. Well know where we came from Why does the universe exist? To put it another way, why is there something instead of nothing? Since the 1920s, scie
24、ntists have known the universe is expanding, which means it must have started at a definite time in the past. They even have developed theories that give a detailed picture of the evolution of the universe from the time it was a fraction of a second old to the present. Over the next couple of decade
25、s, these theories will be refined by data from extraordinarily powerful new telescopes and advances in our understanding of how matter behaves at the unfathomably high temperatures and pressures of the early universe.,BI-OT2,Margaret Geller of the Harvard-Smithsonian Center for Astrophysics, a pione
26、er in exploring the structure of the universe, believes that “by 2100, we will have a complete map of all the galaxies in the visible universe.” Considering that the first primitive maps of North America (produced by explorers who followed Columbus) appeared only 500 years ago, a mere century to map
27、 every galaxy within 15 billion light-years of Earth seems a breathtaking accomplishment.,BI-OT3,2. Well crack the genetic code and conquer cancer In 19th-century operas, when the heroine coughs in the first act, the audience knows she will die of tuberculosis in Act 3. But thanks to 20thcentury ant
28、ibiotics, the once-dreaded, once-incurable disease now can mean nothing more serious than taking some pills. As scientists learn more about the genetic code and the way cells work at the molecular level, many serious diseases cancer, for one will become less threatening. Using manufactured “therapeu
29、tic” viruses, doctors will be able to replace cancer-causing damaged DNA with healthy genes, probably administered by a pill or injection.,BI-OT3,French Anderson of the University of Southern California Medical School, who did the first gene-therapy treatment on a human, predicts that “in 15 or 20 y
30、ears, the majority of diseases will be treatable in this way.” By the end of the next century, people will look at our fear of cancer the way we now look at the operatic fear of TB: as a quaint relic of an immature technology.,BI-OT4,3. Well live longer (120 years?) If the normal aging process is ba
31、sically a furious, invisible contest in our cells a contest between damage to our DNA and our cells ability to repair that damage then 21st-century strides in genetic medicine may let us control and even reverse the process. Experts in this field distinguish between increasing longevity (extending t
32、he average life span now 76.5 years in the United States as we have been doing for centuries) and increasing the maximum possible life span (which seems to be about 120 years). No doubt we can achieve the first, but experts are reluctant to speculate about the second. Says Rita Effros of the UCLA Sc
33、hool of,BI-OT4,Medicine, a leading researcher on aging and the immune system: “I think 120 years of good health is enough for anyone.” So before we push scientists to do more, consider: Do we really want to live in a world where no one grows old and (presumably) few children are born because the pla
34、net can hold only so many people? Where would new ideas come from? What would we do with all that extra time? And would you really want to be a deputy assistant manager for 500 years?,BI-OT6,4. Well “manage” Earth In the next millennium, well stop talking about the weather and do something about it.
35、 David Tilman of the University of Minnesota, a pioneer in developing and testing ecological theories, says, “The worlds ecosystems are incredibly complex, and the job of understanding them is made harder by the fact that they are being changed by the influence of human beings.” As we build bigger a
36、nd faster computers, however, the mystery and unpredictability will start to fade.,BI-OT6,Well gradually learn how to predict the effects of human activity on the Earth, its climate and its ecosystems. And with that knowledge will come an increasing willingness to use it to manage the workings of ou
37、r planet. Earth will be managed, like a farm or a game preserve. The Dutch have been doing this sort of thing on a smaller scale for centuries in managing their system of dikes. I see no reason humanity organized in a global village cant do the same.,BI-OT5,5. Well have a brain “road map” This is th
38、e real “final frontier” of the 21st century: The brain is the most complex system we know. It contains about 100 billion neurons (roughly the number of stars in the Milky Way), each connected to as many as 1,000 others. Early in the next century, we will use advanced forms of magnetic resonance imag
39、ing to produce detailed maps of the neurons in operation. Well be able to say with certainty which ones are working when you read a word, when you say a word, when you think about a word, and so on.,BI-OT7,Steven Pinker of the Massachusetts Institute of Technology, noted psychologist and author of t
40、he book How the Mind Works, predicts that in the next century “well learn a lot about things we dont understand today: human emotions, social relationships, reasoning and decision-making.” Well see new treatments for specific mental conditions (as todays Prozac treats depression). Well develop medic
41、ines that enhance mental functions like the steroids athletes use to promote muscle growth, but without the harmful side effects. So with this fifth prediction we come full circle, and realize that the most difficult thing to understand in the universe may be the 3-pound organ we carry around in our
42、 skulls the organ that allows us to understand the universe in the first place.,BI-MS1,Modern Science (20th century),In the 20th century, scientists achieved spectacular advances in the fields of genetics, medicine, social sciences, technology, and physics.,1. GeneticsAt the beginning of the 20th ce
43、ntury, the life sciences entered a period of rapid progress. Mendels work in genetics was rediscovered in 1900, and by 1910 biologists had become convinced that genes are located in chromosomes, the threadlike structures that contain proteins and deoxyribo-nucleic acid (DNA). During the 1940s Americ
44、an biochemists discovered that DNA taken from one kind of bacterium could influence the characteristics of another. From these experiments, it became clear that DNA is the chemical that makes up genes and thus the key to heredity.,BI-MS2,After American biochemist James Watson and British biophysicis
45、t Francis Crick established the structure of DNA in 1953, geneticists became able to understand heredity in chemical terms. Since then, progress in this field has been astounding. Scientists have identified the complete genome, or genetic catalog, of the human body (see Human Genome Project). In man
46、y cases, scientists now know how individual genes become activated and what effects they have in the human body. Genes can now be transferred from one species to another, side-stepping the normal processes of heredity and creating hybrid organisms that are unknown in the natural world (see Transgeni
47、c Organism).,BI-MS3,2. MedicineAt the turn of the 20th century, Dutch physician Christiaan Eijkman showed that disease can be caused not only by microorganisms but by a dietary deficiency of certain substances now called vitamins. In 1909 German bacteriologist Paul Ehrlich introduced the worlds firs
48、t bactericide, a chemical designed to kill specific kinds of bacteria without killing the patients cells as well. Following the discovery of penicillin in 1928 by British bacteriologist Sir Alexander Fleming, antibiotics joined medicines chemical armory, making the fight against bacterial infection
49、almost a routine matter. Antibiotics cannot act against viruses, but vaccines have been used to great effect to prevent some of the deadliest viral diseases. Smallpox, once a worldwide killer, was completely eradicated by the late 1970s, and in the United States the number of polio cases dropped fro
50、m 38,000 in the 1950s to less than 10 a year by the 21st century.,BI-MS4,By the middle of the 20th century scientists believed they were well on the way to treating, preventing, or eradicating many of the most deadly infectious diseases that had plagued humankind for centuries. But by the 1980s the
51、medical communitys confidence in its ability to control infectious diseases had been shaken by the emergence of new types of disease-causing microorganisms. New cases of tuberculosis developed, caused by bacteria strains that were resistant to antibiotics. New, deadly infections for which there was no known cure also appeared, including the viruses that cause hemorrhagic fever and the human immunodeficiency virus (HIV), the cause of acquired immunodeficiency syndrome.In other fields of medicine, the diagnosis of disease has been revolutionized by the use of new imaging techniques,
