1、导读话题妙切入UNIT 4 NATURAL DISASTERS1Unity is strength.团结就是力量。2The first in time and the first in importance of the influences upon the mind is that of nature.Emerson在所有对头脑的影响之中，大自然的影响可谓在时间上最先，在作用上最为重要。爱默生3There is kindness to be found everywhere.人间处处有温情。4The earth is our only home-planet.地球是我们唯一的家园。5The
2、 fear of the disaster is worse than the disaster itself.对灾难的恐惧比灾难本身更可怕。Never give upNever give up，Never lose hope.Always have faith，It allows you to cope.Trying times will pass，As they always do.Just have patience，Your dreams will come true.So put on a smile，Youll live through your pain.Know it will
3、 pass，And strength you will gain.Now,lets talk about earthquakes on our planet.Some countries have large numbers of earthquakes.Japan is one of them.Others do not have many.For example,there are few earthquakes in Britain.There is often a great noise during an earthquake.The ground vibrates(震动).Hous
4、es fall down.Trains run off the lines.Sometimes,there is a heavy loss of human lives.Earthquakes often happen near volcanoes,but this is not always true.The centers of some earthquakes are under the sea.The bottom of the sea suddenly moves.The powerful forces inside the earth break the rocks.The coa
5、st is shaken and great waves appear.These waves,also known as seismic waves (地震波)or tsunamis,can travel long distances and rush over the land when they reach it.They are strong enough to break down houses and other buildings.Very often fires follow the most serious earthquakes.In the 1906 San Franci
6、sco earthquake,a numbers of fires were burning in the city.The water pipes were also shaken and broken,so it was not possible to put the fire out.There was no water.The Tokyo Earthquake of 1923 happened just before noon.People were cooking meals on their fires at that time.When the ground shook,the
7、fires shook,too.Hot materials were thrown on the different parts of the houses,some of which were made of wood.Soon 134 fires were burning in the city.What kind of building stands up best in an earthquake?A building with concrete walls is perhaps the best.A steel frame will make it even stronger.The
8、 frame holds the different parts together and the walls will not easily fall.There is less chance of fire because concrete and steel do not burn.Over the years，scientists studied the results of earthquakes in different parts of the world,and they are sure that this kind of building is the safest.探索发现1Find out the main topic of the passage._2Find out what may cause undersea earthquakes._3Find out the main idea of the last paragraph._Earthquakes.The powerful forces inside the earth.A building with concrete walls and a steel frame stands upbest in an earthquake.谢谢观看 THANK YOU!
