九年级英语第二十单元

　　科目 英语

　　年级 初三

　　文件　middle3 unit20.rar

　　标题 初三第二十单元

　　章节 第二十单元

　　关键词

　　内容

　　一．教学目标

　　3.句型:

　　1)Make sure that it is straight.

　　2)Put the tree in the hole so that it is straight.

　　3)The ground must be just right---neither too wet nor too dry.

　　4)It's best to plant trees in spring.

　　5)It's ten metres long/wide/deep/high.

　　6)There are twenty more trees to be planted.

　　4.日常用语:

　　1)Will you help me plant this tree,please?

　　Of course. What do you want me to do?

　　2)Is it straight? More or less>

　　3)That's done. What's the next?

　　4)The more, the better.

　　二．教学重点

　　1.含有情态动词的被动语态

　　2.neither...nor; stop...from doing sth; 等

　　3.部分日常用语

　　三．教学难点

　　含有情态动词的被动语态

　　四．重点难点讲解

　　1．_ neither too wet nor too dry. 既不要太潮湿也不要太干燥。

　　both 和neither

　　1)both表示"两者都"，即指两个人或物，是复数概念；neither"两这种无一"，也指人或物，然而是单数概念。因此，both修饰复数名词，谓语用复数形式；neither修饰单数名词，谓语用单数形式。如：

　　Both answers are right. 两个答案都对。

　　Neither answer is right. 两个答案无一是对的。

　　（第二句是第一句的全否定形式。它的不完全否定形式是这样的，

　　Both answers are not right. 两个答案并不都对。）

　　I like both of them. 他们两个我都喜欢。

　　I like neither of them. 他们两个我都不喜欢。

　　（如果数量是三个或三个以上，则肯定句用all,否定句用none。如：

　　All of them are interested in it. 他们对此都感性趣。

　　None of them are(is) interested in it. 他们对此都不感性趣。

　　2）both...and...和neither...nor...可以连接两个并列成分，即两个主语，谓语，宾语或其他并列成份。如：

　　She can both sing and dance. 她既会唱歌又会跳舞。

　　She can neither sing nor dance. 她既不会唱歌又不会跳舞。

　　Both Tom and John are from Britain. Tom 和John都是英国人。

　　Neither Tom nor John is from Britain. Tom和John 都不是英国人。

　　（both...and...连接两个主语时，后面谓语用复数。而neither...nor...连接两个主语时，后面 谓语必须与nor后面的主语在数上保持一致。如：

　　Neither Jack nor his parents are interested in the girl.

　　Jack和他的父母对那个女孩都不感兴趣。

　　2．happen to sb./sth.

　　表示某人或某件事情发生了什么情况。很多时候表示一种偶然性。

　　happen的主语一般是疑问代词what ，不定代词something, anything,nothing,以及某些表示消极意义的名词。

　　happen是不及物动词，不能用于被动语态。

　　Happen总是和介词to搭配。如：

　　1)What has happened to Mary? She isn't here yet.

　　Mary出了什么事？她现在还没到。

　　2）If anything happens to the machine,please let me know.

　　如果机器出了什么毛病，请通知我。

　　3）The accident happened to him at three this afternoon.

　　他出事是在今天下午三点半。

　　3．... about a third was... 大约三分之一是.......

　　分数的表达法

　　分子用基数词，分母用序数词。如果分子是二或二以上的数，分母加-s.如：

　　one-third 三分之一

　　two-thirds 三分之二

　　分数作主语，谓语的单复数取决于它所代表的量是单数还是复数。如：

　　Three-fourths(Three quarters)of the students of our school are boys.

　　我们学校四分之三的学生是男生。

　　Three quarters of the work has been done.

　　工作的四分之三已经完成。

　　4．hundred和hundreds of

　　hundred前面可以用表示具体概念的数词来修饰。而hundreds of表示"多"， "数以......计"，前面不可一家表示具体概念的数词。如：

　　There are two hundred students in our grade. 我们年级右二百个学生。

　　Several millions of trees are planted in our country every year.

　　我国每年将种植好几百万棵树。

　　5．Stop...from doing

　　stop sb./sth.from doing sth.是"阻止......不作某事"，介词from可以省略。如：

　　We must stop him (from)doing such a foolish thing.

　　我们必须阻止他不让他作这样的蠢事。

　　They tried to stop such a thing (from)happening.

　　他们向阻止这样的事情发生。

　　6．stop to do和stop doing

　　stop to do的意思是"停下来做事情"，不定式做状语。

　　stop doing的意思是"停止做事情"。如：

　　They stopped to talk to me. 他们停下来和我讲话。

　　Stop running about! 不要乱跑。

　　7．the more, the better越多越好。

　　前一分句表示假设，条件，时间等，后一分句表示结果。如；

　　The more you read,the more you will get. 你读的越多，得到的也就越多。

　　The farther he walked, the stranger he felt. 她越往前走，越感到奇怪。

　　8．thanks to ... "多亏了......","由于......帮助"。如：

　　Thanks to the English language, we can learn a lot from English-speaking countries.

　　由于英语这门语言的帮助，我们能够向说英语的国家学到许多东西。

　　I've passed the exams thanks to my teachers. 多亏了我的老师，我通过了这次考试。

　　9．不定式作定语

　　1）I have a lot to do today. 我今天有许多事情要做。（a lot是do的逻辑宾语）

　　2）I have three letters to write this evening. 今晚我有三封信要写。

　　3）She is a nice person to work with. 她是一个很好共事的人。

　　4）Let's find a room to put these things in. 我们找个房间把这些东西放在里边。

　　（前两个例句的不定式是及物动词，后两个例句的不定式时不及物动词，它后面就应加上必要的介词。）

　　10....as often as possible 尽可能常......

　　as soon as possible 尽可能地快

　　as far as possible 尽可能地远些

　　11．Today, too many trees are still being cut down in the USA.

　　今天在美国人有大量树木继续被砍伐。

　　be+being+过去分词是现在进行时的被动语态，表示"正在被......" 如：

　　The silk is being produced by the factory. 这个工厂正在生产丝绸。

　　12．The Great Green Wall is 7,000 kilometres long, and between 400 and 1,700 kilometres wide.

　　这绿色长城长为7，000公里，款再次00指，700公里之间。

　　表示计量的方法是：数词+metres/kiometres+long/wide/deep/high/tall...

　　表示重量可用数词+kiograms+heavy 如：

　　The class room is 4 metres wide. 这个教室有4米宽。

　　The river is about 10 metes deep. 这条河有10米宽。

　　13．There are twenty more trees to be planted!

　　还有20可树要种呢！

　　to be planted是动词不定式的被动式，作明词trees的定语。动词不定式作定语时，通常放在被修饰名词之后。如：

　　We have a lot of food to eat. 我们有许多食物可吃。

　　I have many books to read. 我有许多书要看。

　　同步测试

　　一.用所给词的适当形式填空

　　1.Come to school in ______ old clothes tomorrow. (you)

　　2.About half of the USA was ____ by forests. (cover)

　　3.The more, the ___- .(good)

　　4.People have planted a large number of trees in the _____ part of China. (north)

　　5.The old farmer is _______ his horse to the tree. (tie)

　　6.More vegetables should be ______ in the village. (grow)

　　7.The river is ten meters _____ than that one. (deep)

　　8.Grandpa _____ flowers every morning. (water)

　　9.The railway is ____ of kilometers long. (million)

　　10.Look. How _____ the little girl is dancing! (wonderful)

　　(1.your 2.covered 3.better 4.northern 5.tying 6.grown 7.deeper 8.waters 9.milliona 10.wonderfully)

　　二.选择填空

　　or, away, knock, take, so that, make sure, save, build, copy. push

　　1.How far ___ is Australia from China?

　　2.____ that you will be free next Sunday.

　　3.China does not want _____ the USA's example.

　　4.Great Green Walls must ____ all over the world.

　　5.The Great Green Wall has already ______ a lot of farmland.

　　6.Trees should _____ good care of.

　　7.Go to bed early ______ you can get up early tomorrow morning.

　　8.I _____ a stick into the earth at that time.

　　9.Work harder _____ you won't pass the exam.

　　10.______the earth down hard with your foot several times.

　　(1.away 2.Make sure 3.to copy 4.be built 5.saved 6.be taken 7.so that 8.was knocking 9.or 10.Push)

　　三.阅读短文，根据内容选择适当的答案

　　The Indians breathe thin air. The air goes up for thousands of miles. The higher the air goes up, the thinner it gets. Thin air is hard to breathe.

　　People who go up into high mountains often get dizzy. Breathing the thin air makes them dizzy.

　　A man is flaying more than 15,ooo feet above the sea. The air is very thin. Is the man dizzy? No. He is breathing oxygen from a tank.

　　In south America, Indians live far up on the mountains. Their homes are more than 15,000 feet above the sea. The Indians are not breathing oxygen from a tank. But they do not get dizzy. They have lived in these mountains all their lives. Their lungs have changed. They have become large. The large lungs help the Indians breathe the thin air.

　　Sometimes the Indians go down to the low country, People living down there feel fine. But the Indians feel sick.

　　( )1.What does the sentence "The higher the air goes up, the thinner it gets."mean?

　　A.It means that you can get thin air when you are tall enough.

　　B.It means that the air in a high place is as thin as that in a low place.

　　C.It means that the air vecomes thinner in a higher place.

　　( )2.Why so people often get dizzy when they go up ;into high mountains?

　　A.Because they are too tired./

　　B.Because there is less oxygen in the air.

　　C.Because their lungs becomes smaller.

　　( )3.Mountain Indians can breathe thin air because______.

　　A.they have larger lungs than common people.

　　B.they need less oxygen than common people.

　　C.they are much stronger than common people

　　( )4.From the passage we know_____.

　　A.it is hard for all the people to breathe thin air.

　　B.it is hard for Indians to breathe thin air.

　　C.it is hard for those who live in lower places to breathe thin air.

　　( )5.The main idea of this passage is _______.

　　A.people get used to the air where they live

　　B.air is very important

　　C.the Indians who live in high mountains.

　　(CBACA)