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d nineteenth centuries .(slide show)
Step II. Reading
1. Skimming let Ss read the passage carefully and answer the question:
Why did Benjamin Franklin do this experiment with the kite?
(He wanted to show /prove that lightning and electricity are the same thing.)
2. Skipping let Ss read the passage again, and finish the following exercises: (slide show)
True (T)or false (F)
1. In 1752 scientists already knew what electricity is. (T )
2. Franklin was helped by a friend to do the experiment. (F )
3. Franklin made the kite of silk because wet silk does not conduct electricity. (F )
4. A condenser was used in the experiment to store electricity. ( T )
5.The key tied to the string was put into the door to stop the kite form flying away. (F )
3. Extractive reading let Ss read the passage carefully, and answer the following the questions:
a.why is it better to make the kite of silk than of paper?
(A slik kite will last longer in bad weather than a paper kite. )
b. Do you think Franklin’s experiment was dangerous? Explain.
(Yes Franklin’s experiment was very dangerous because if something went wrong he could be killed by the lightning. )
4. let Ss find out the keys of the exercises after their reading.(slide show)
Aim: To show that lightning and electricity are the same.
Materials: Some wooden sticks, a piece of silk, some rope, a very sharp piece of metal, a silk ribbon, a key, a condenser, a small shed, a thunderstorm with lightning.
Results: The electricity stored in the condenser can be used to do other experiments, which proves that lightning and electricity are the same.
4. listening play the tape and let Ss follow, paying attention to the intonation.
Step III Discussion
T says: In order to conduct science experiments, scientists must often find practical solutions to overcome problems, make large scale natural phenomena manageable and think about their own safety.
Let Ss work in group and discuss how Franklin used his creativity to overcome various problems for his experiment
1. We cannot go and look for lightning ,so Franklin has to find a way to make lightning come to him: he attracted lightning using a kite.
2. A kite made of paper won’t last long in rainy weather, so he had to make a strong kite: he made his kite of silk.
3. A silk kite doesn’t attract lightning, so he had to add something: he fixed a long, sharp piece of metal to the top of the longest stick of the cross.
4. He had to collect and store the electricity, so that he could later use it in other experiments: he brought a condenser.
5. He had to make sure that he himself would not be hit by the lightning, so he had to find a low place where he could keep himself and his tools dry: he used a small shed in the fields
6. He had to stop the kite from flying away, without touching the string that would be charged with electricity: he tied a silk ribbon to the string that he kept dry by standing inside the shed. Dry silk doesn’t conduct electricity, so it was safe to hold it in his hands.
7. He had to direct the electricity towards the condenser, with piece of metal at the end of the string: he tied a metal key to the end of the string.
Step IV Post-reading
Translate the following sentences into English.(slide show)
1、弗兰克林的风筝实验表明，闪电和电是一码事。（experiment）.
2、有些人认为，和能源对环境构成的威胁远远超出它给社会带来的益处。（nuclear energy）
3、轻微的电击对人体无碍，但强电却能致人死命。（electric shock）
4、关于这位科学家的家庭生活，众说纷纭。（a great deal of）
5、你怎么证明你没干这件事？（prove）
6、作为人类最早的发明之一，轮子至今仍在人类活动中发挥着重要作用。（wheel）
7、琳达很生气，把信撕成碎片，扔进了垃圾筐。（tear）
8、根据英国法律，每一种新药必须在至少两种不同类的动物身上试验。（test on）
1. Franklin’s kite experiment showed that lightning and electricity are the same.
2. Some people think that the threat that nuclear energy forms to the environment weighs much
more than the good it does for society.
3. A light electric shock does no harm to the human body, but a strong one can kill.
4. There was a great deal of talk about the scientist’s family life.
5. How can you prove that you didn’t do it?
6. The wheel, one of the earliest inventions, still plays an important role in human activities.
7. Linda was so angry that she tore the letter into pieces and threw them into the dustbin.
8. British law says that every new drug must be tested on at least two different kinds of animals.
Step V. Language points and useful expressions
Decide to do sth. Do one’s experiment.
Begin to Stand up
Get charged A great deal of
Prove Be made of
Protect…from… Come on
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