Long ago,people made up interesting stories to explain what causes lighting and "thunder".To many people,lighting and thunder can be very frightening especially because they often happen just before a big rainstorm.Actually,having a better understanding of something can make it less frightening.
Lightning is caused by electricity building up inside a cloud.When a large amount of warm air and cold air come together high above the earth,it causes a lot of movement in the air.The cold air moves down while the warm air moves up,which creates something like friction（摩擦）.An electric charge builds up in the clouds.The charge gets stronger and stronger until the explosion（爆炸）happens--and the LIGHTING flashes.
When the lighting flashes,the air around it becomes unbelievably hot--five times hotter than the surface of the sun!The heated air becomes larger and larger and gets into the cooler air around it,causing the big shock wave that we call thunder.We now know what causes lighting and thunder.Have you ever noticed that you often hear thunder just a few seconds after you see lighting?In a joke,people even said the reason was our eyes are in front of our ears!In fact,that\’s because it is lighting that causes thunder.If the storm is far away from you,there are a few second between the lighting and the thunder.If the storm is close to you,you hear the thunder almost at the same time that you see the lighting.
Even though we usually see lighting before we hear the thunder that it causes,the two events happen just a fraction（部分）of a second（瞬间）apart.In addition,both light and sound travel through the air in waves.However,light waves travel faster than sound waves,so the light waves from the explosion（爆炸声）get to us first.
In our daily life,something similar to lighting and thunder can happen when you brush your feet along a carpet（地毯）and then touch a doorknob.You can sometimes hear the little sizzle（咝咝声）of mini-thunder,and see the flash of mini-lightning.
（1）Why did the writer talk about people making up interesting stories in the first paragraph? ______
A.To lead in the topic of this passage.
B.To help readers become less afraid of the nature.
C.To get people interested in the stories about lightning and thunder.
D.To help readers better understand the stories behind lightning and thunder.
（2）What is " thunder" according to the passage? ______
A.An explosion developed by air friction.
B.A sound created by electricity in the air.
C.A heat produced by the surface of the sun.
D.A large wave caused by the growing heated air.
（3）Which of the following is the correct order of lightning and thunder\’s happening? ______
①The air around it becomes five times hotter than the surface of the sun.
②An electric charge gets stronger and stronger,then the explosion happens.
③It causes a lit of movement in the air when warm cold air come together high above the earth.
④The shock wave called thunder happens when the heated air becomes larger and larger and gets into the cooler air around it.
A.②①③④
B.③②①④
C.③②④①
D.①④③②
（4）Why do we usually hear thunder a few seconds after seeing lighting? ______
A.We are very close to the storm.
B.Our eyes are in front of our ears.
C.Lightening is the cause of thunder.
D.Sound waves travel faster than light waves.
（5）What can we learn about lightning and thunder from the last paragraph? ______
A.They can be seen and heard anytime anywhere.
B.Things like them might also happen around us.
C.We should be careful and not get hurt by both of them.
D.Brushing your feet along a carpet can be very dangerous.