高二英語(yǔ)必修五Unit 1 Great scientists教案

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 answer 1:
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: 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 3:
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 ⅳ 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.