某中学高考英语-Unit4-(Warming-up)复习课件.ppt

1、Lead-in:Lead-in:Do you know what natural disaster happened in South Asia on October 8?I.Look carefully at the two pictures.Describe what you see in the pictures.But unfortunately,in 1906 a big earthquake happened in San Francisco.Whats worse,a bigger earthquake happened in Tangshan in 1976 in China.

2、Imagine what might have happened to all the things in the photos.Houses fell down.Bricks covered the ground.Brick buildings were destroyed.Factories,hospitals,schools,and the other buildings were gone and lost.Roads got huge cracks.Many buses were caught in them.A huge crack might have cut across ho

3、uses,roads and canals.Steam burst from holes or wells in the ground.Water pipes cracked and burst,so the water supply was cut off.The smoke of fires could be seen.The electricity lines were destroyed.The electricity supply was also cut off.Bridges and dams fell down or were not safe for travelling.R

4、ailway tracks were useless pieces of steel.The transportation was delayed.Many people died and were injured.Families were killed and many children were left without parents.The survivors became homeless.Workers built shelters for survivors whose homes had been destroyed.In a few terrible seconds,a l

5、arge city lay in ruins.Everything was destroyed.It seemed that the world was at an end.Tips about the earthquakeThe Richter(力克特震级)and its damage How strong is the earthquake How much damage Less than 3.5 3.5 5.4 Under 6.0 6.1-6.9 7.0-7.9 8-greater not felt but recorded by scientists often felt but d

6、oesnt cause damage most light damage to strong buildings;can cause great damage to weak buildings in a small area can destroy buildings in areas up to about 100 kilometers across where people live very strong earthquake;can cause much damage over larger areas great earthquake;can cause serious damag

7、e in areas several hundred kilometers across II.What do you think may happen before an earthquake?People can see bright lights in the sky.The sound of planes can be heard outside even when no planes are in the sky.Mice will run out of the fields looking for places to hide.Fish will jump out of the b

8、owls or ponds.Animals will be too nervous to eat.Farmers wives will notice that the well walls have deep cracks in them.The water will rise and fall,rise and fall for a few days,steam will burst from holes or wells in the ground.III.Why do earthquakes happen?Listening:1.Listen to the tape the first

9、time and then say True or False to the following sentences.1)Inside the earth there are a number of plates.2)These plates move all the time.3)If they stop moving there is an earthquake.4)If they jump there is an earthquake.5)China is in an earthquake area.6)The Pacific plate is pushing on China from

10、 the east.7)The Himalayan mountains were caused by the movement of plates.8)Human beings have the power to stop earthquakes.2.Listen again and choose the best answer.1)The Pacific plate is moving at _.A.3.5cm a year B.5.3cm a year C.35cm a year D.53cm a year2)When the 1906 earthquake happened,the Pa

11、cific plate suddenly jumped _ to the north.A.4-5 meters B.3-4 meters C.5-6 meters D.7-8 meters3)The India plate is pushing on China from _.B.southwest to northeast B.northeast to southwestC.southeast to northwest D.northwest to southeast4)Which one of the following cant reduce losses from earthquake

12、s?A.not building where plates meet B.building on rockC.building strong houses D.building weak housesListening tex Why do earthquakes happen?Scientists explain that the outside of the earth is made of a number of different plates.At San Francisco,the Pacific plate which is moving towards the northwes

13、t meets the North American plate.The Pacific plate moves very slowlyat 5.3 centimetres a year.Sometimes these two plates stop and do not move for years.Then suddenly,they jump and an earthquake is felt.As a result of the movement of these plates,California has always had a lot of earthquakes.When th

14、e 1906 earthquake happened,the Pacific plate jumped 5-6 metres to the north.China also has an unlucky place on the earth.The Pacific plate is also pushing on China from the east as the plate moves west.Likewise,the Indian plate is pushing on China from the southwest as that plate moves northeast.The

15、 same power that produced the great Himalayan Mountains now causes earthquakes in China.We cannot stop earthquakes,but we can do things to make sure they do not destroy whole cities.First,it is not a good idea to build houses along the lines where two of the earths plates join together.Second,if you

16、 think there may be an earthquake,it is better to build houses on rock than on sand.Third,you must make the houses as strong as possible.Weak buildings will fall down in an earthquake,but strong ones may stay up.Summary:From this period,we know some knowledge of earthquakes in three ways:_ caused by

17、 earthquakes,_ before earthquakes and _ why earthquakes happen.the damagethe signsthe reasonHomework:Homework:1.Preview the passage of Page 26,and try to finish the exercises of Page 27.2.Read and remember the new words and expressions of this unit.3.Find some information about Tangshan in groups.Thank you!