1、Unit 4 Life in Mars第3课时 Reading 1.To learn some language points in the text.2.To be able to finish some exercises according to the text.Studying aims1.By 2100,people might live on Mars.2.Mars is becoming crowded and polluted.3.Now,it takes months for a spacecraft to travel from earth toMars.4.People
2、 are not sure whether there would be eongh water ofoxygen on Mars.TFTTRead and tell T or F:Revisionearth5.Mars has one-eighth the gravity of Earth.6.People will have less space on Mars.7.Students will go to school by spacecraft.8.People might have to do housework by themselves.FFFFthree-eighthsmores
3、tudy in online school.dont have to doRevisionAnswer the following questions about the life on Mars.1.When will people move to the planet Mars?2.Why will we leave our own planet Earth?By the year 2100.Because Earth is becoming more and more crowded and polluted.Revision3.How long does the spacecraft
4、need to get to Mars at present?4.How long does the spacecraft need to get to Mars in the future?What would food on Mars be like?It takes months.About 20 minutes.Food would probably be in the form of pills and would not be so tasty.RevisionFill in the blanks with proper words.Our own planet,earth,is
5、becoming more and more _ and _.Hopefully,we can build a better world on _ by the year 2100.At present,our spacecraft are too slow to carry large numbers of _ to Mars.By 2100,the _might take only 20 minutes in spacecraft that travel at the speed of light.crowdedpollutedMarspassengersjourneyRevisionFo
6、od on Mars would probably be in the _ of pills and wound not be so _ as that on the Earth.Gravity could be another problem for people on Mars.The gravity on Mars is only about_ of that on the Earth.People on Mars have to wear special_ to prevent themselves from_off into the space.formtastythree-eigh
7、thsbootsfloatingRevision1.Our own planet,the Earth,is becoming more and more crowded and polluted.more and more crowded 越来越拥挤这里，more and more 用来加强程度，表示越来越怎么样。相当于：more crowded and more crowded而短形容词则这样构成：bigger and bigger Language pointscrowded用作形容词，意为“拥挤的”。be crowded with意为“充满，挤满”。如：The room was crow
8、ded with guests.房间里挤满了客人。The bus was so _(拥挤的)that I didnt get on it.crowdedLanguage points(1)“Food Safety”problem is becoming _ these days.I think so.The government must do something to deal with it.Asmaller and smallerBworse and worseCbetter and betterDnicer and nicerBPractice(2)How do you improve
9、 your English?_ you speak,_ your English will be.AThe less;the moreBThe more;the betterCThe less;the betterDThe more;the lessBPractice2.At present,our spacecraft are too slow to carry large numbers of people to Mars.(1).too+adj.+to do Sandy 太小了而不能去上学。Sandy is too young to go to school.so.that.cant.S
10、andy is so young that she cant go to school.not adj.+enough to do.Sandy is not old enough to go to school.Language pointslarge numbers of 许多，大量，修饰_名词，做主语时，谓语动词常用_形式，相当于a lot of,many。eg.Large numbers of birds fly to the south every winter.3.large numbers of.manythe number of 的数目 后常接可数名词复数，做主语时，谓语动词常用
11、单数形式。=可数 复数 eg.The number of tourists starts to tail off in October.游客在十月份开始逐渐减少。Language points(1)China has _ of people.(2)_ of the population of china is 1.3 million.(3)_ my friends came to my birthday party.a(large)number The number A number ofLanguage points探究 speed意为“速度”，短语at a/the speed of，意为“
12、以的速度”。at a high/full speed意为“_”。at a low speed意为“_”。The car ran at a very slow speed.那辆小汽车以非常缓慢的速度行驶。以高速/全速 以缓慢的速度 4.at the speed of 以的速度 Language points5.观察 The gravity on Mars is only about three-eighths of that on Earth.火星上的重力大约只有地球上的八分之三。探究 threeeighths意为“八分之三”。英语中分数的表达法：分子用_，分母_；分子大于1时，分母变为_形式；
13、分子与分母之间可加连字符，也可不加。1/3 one third 2/5 twofifths基数词 序数词 复数 Language points拓展 分数后面常跟of 短语，作主语时，谓语动词的单复数和of 后面名词的单复数保持一致。Threefourths of the land is covered by forests in that country.那个国家四分之三的土地被森林覆盖着。翻译句子:我们班五分之三是女生。_ the students in my class_ girls.Three-fifths ofareLanguage points6.prevent sb(from)do
14、ing sth意为“_”，与stop sb(from)doing sth和keep sb from doing sth同义。(其中keep sb from doing sth 的from不可省略，省略后，其意义发生变化。即：keep sb doing sth意为“_”)三者用于被动语态时，from都不能省略。The heavy rain prevented/stopped/kept him from_(come)to school on time.这场大雨使他没能按时到校。Im sorry to keep you _（wait）for a long time.我很抱歉让你等了很长时间。阻止某人
15、做某事 让某人一直做某事 waitingcomingLanguage points7.Compared with life on Earth,life on Mars would be better in some ways.与在地球上的生活相比,火星上的生活在某些方面要好些。compare with 意思是“与做比较”。在句中是过去分词短语作状语,此时with和to可通用。Language pointsTranslate the following phrases.以的速度_ 2.飘进太空 _ 3.现在，目前 _pare with _ 5.large numbers of _at the s
16、peed offloat off into spaceat present与比较 许多的，大量的 exercisesB.Fill in the blanks with the correct forms of the words in the bracketsWe had a _ meal with her last night.(taste)The river has been _ by waste water from the factory.(pollution)We will be a bit _ in that small room.(crowd)Humans on Mars have to wear special shoes to prevent themselves from_.(float)tastypollutedcrowdedfloatingexercises1.Search for more information about Mars on the Internet2.Tell others to take action to protect our earth3.Read the passage about MarsHomework谢谢观看
