Unit 1 Great scientists The First Period warming up and reading

Teaching goals教學目標

1.Ability goals 能力目標：Enable the students to talk about science and scientists. 2. Learning ability goals學能目標：Enable the students to learn about some famous scientists and their contributions and how to organize a scientific research.

Teaching important difficult points教學重難點：Talk about science and scientists.

Teaching procedures ways 教學過程與方式

StepⅠ Lead-in：Ask the students to think of some great inventions and inventors in history.

Step II Pre-reading：Get the students to discuss the questions on page 1 with their partners. Then ask the students to report their work. Encourage the students to express their different opinions.T： Now， class， please look at the slide. Discuss these questions with your partners. Then I'll ask some students to report their work.

Show the following on the screen.What do you know about infectious diseases？ What do you know about cholera？ Do you know how to prove a new idea in scientific research？ What order would you put the seven in？ Just guess.

Sample answer1：

S1： Let me try. Infectious diseases can be spread easily. They have an unknown cause and may do great harm to people. S2： People could be exposed to infectious diseases， so may animals， such as bird flu. S3： AIDS， SARS are infectious diseases. S4： Infectious diseases are difficult to cure.

Sample answer 2：

S1：Cholera is caused by a bacterium called Varian cholera. S2： It infects people’s intestines， causing diarrhea， vomiting and leg cramps. S3： The most common cause of cholera is people eat food or drink water that has been contaminated by the bacteria. S4： Cholera can be mild or even without symptoms， but a severe case can lead to death without immediate treatment.

Sample answer 3：

S1： I know sth. about it. First we should find the problem. Then， think of a solution. S2： We should collect as much information as possible. S3： Analyzing results is the most important stage. S4： Before we make a conclusion， it is necessary for us to repeat some stages or processes.

Sample answer 4：

S1： I think “Find a problem” should be the first stage. S2： “Make up a question” should follow the first stage. S3： “Think of a method”，“Collect results” and “Analyze results” are after that. S4： Of course， before “Make a conclusion”， we should “Repeat if necessary”.T： Well done！ When we want to solve some problems， first we should find out the problem， do some research on it， prove your findings， and then make a conclusion. This is a scientific and objective way of researching. Now let’s see how doctor John Snow did his research.

Step Ⅲ Reading

Let the students skim the whole passage and try to work out the meanings of the new words and structures using context.

T： The effect of cholera in the nineteenth century London was devastating. Many people died without knowing the reason. It was doctor John Snow who saved the people. Please look at the screen. Let’s read the whole passage and find answers to the questions.

Show the questions on the screen.

1. What conditions allowed cholera develop？ 2. Why do you think people believed that cholera multiplied in the air without reason？ 3. What evidence did John Snow gather to convince people that idea 2 was right？

Sample answers：

S1： The dirty water made the cholera develop quickly. S2： Because people could not understand its cause and could not get it cured. So people imagined that some poisonous gas in the air caused the deaths. S3： He found that many of the deaths were near the water pump while some areas far away from the water pump had no deaths. So when people were asked not to use the water pump， the disease began to slow down. In this way， John Snow had shown that cholera was spread by germs and not in a cloud of gas.

Step VI Text analyzing（PPT）（小組展示）： Read the passage and divide the whole passage into several parts and find out the main idea.

Part 1. The harm of Cholera： Many thousands of terrified people died every time there was an outbreak. The problem ： Neither its cause nor its cure was understood. Part 2. The likely reasons： Cholera spread in the air.People absorbed this disease into their body with their meals. Part 3. The way of researching： By enquiring and gathering information on a map. Part 4. What he found： many deaths were near the water pump.some houses had had no deaths. His preliminary（初步的） conclusion： water was to blame. Part 5. What to do？ what to find？ looked into the source of their drinking water

→found it came from the river polluted by the dirty water from London.told people to remove the handle from the pump.→ found the disease slow down

Part 6. What is the supporting evidence？ Two other people in another part of London died after drinking the water.His final conclusion： announced with certainty that polluted water carried the virus.

Part7.What did John do after his discovery？suggested that the water supplies be examined. The water companies were instructed not to expose people to polluted water.

知識拓展： Fill in the blanks and retell the text：（PPT）： John Snow was a well-known doctor/physician in London in the 19th century. He wanted to find the __cause__ of cholera in order to defeat_it. In 1854 when a cholera broke out， he began to gather information. He marked on a map where all the dead people had lived and he found that they had drunk the water from the _pump nearby. Then he ___looked into__ the source of the water and found it came from the river _polluted_ by the dirty water from London. Later， he also found two other deaths in another part of London were _linked to the water. So he announced certainly that polluted water carried the virus.Besides， he suggested that the source of all water supplies be _examined. And the water companies were _instructed to provide people with clean drinking water.