参考教案 教学建议
教学建议 (Suggested teaching notes)
一、教学内容分析
本单元教学内容主要围绕“Planting trees”这个主题来展开。学生在已学习了一般现在时和一般过去时被动语态的基础上，继续学习含有情态动词被动语态的构成和用法，加深他们对被动语态的整体感知。同时学习一个新的语言点--计量 (Measurement) 的表达法。第69课通过一段对话来引入本单元主题“Planting trees”，然后提供了一篇有关种树的注意事项。其中大部分句子含有带情态动词的被动语态，以此来引入本单元语法教学的重点。
第70课是一篇题为“THE GREAT GREEN WALL”的文章。学生们在阅读、学习这篇文章后，对本单元的主题有了进一步的了解，继续巩固他们对带情态动词的被动语态的认识并开始学习计量的表达法。教师在教学本课时，应注意让学生整体把握课文大意，同时教给他们一些阅读技巧。
第71课由三段句型操练组成，旨在巩固学生的语法和词汇知识，让他们能够熟练运用这些知识。
第72课的听力材料和三段对话也是围绕植树的主题设计和编排的，为教师和学生提供了进一步操练和交际运用的素材。本单元的语言重点通过复习要点作了总结。
二、教学方法建议
（一）口语教学
本单元第69课以Read and act的形式来引出本课的教学重点。教师应充分利用这个对话情景，进行对话表演，以提高学生的兴趣，达到自然地呈现新课的目的。
教师在上课时，可穿一件旧衣服或工作服，问学生，“I came to school in／I'm wearing myold clothes today. Tomorrow you will come to school in your old clothes. Do you know why?”这时，学生们可以进行多种猜测。在学生情绪高涨时，教师让他们带着问题听课文录音。在听第一遍录音后，利用本课挂图，再让学生听一至两遍录音。为了帮助他们更好地理解对话的内容和句型，教师此时可将一些关键词写在黑板上，如：in old clothes, What's happening? TreePlanting Day, Really? Wonderful!在学生了解了对话的基本内容后，教师可放录音让全班跟读或分角色对话。然后两人一组借助黑板上的关键词来复述或表演。注意这段对话的主要目的是引出下面的“instructions”，而且对话中新的语言知识不多，所以不必占用过多的时间。
第72课在Read and act下也有3段对话。但与第69课对话不同。这时学生已学完本单元的语法重点和阅读文章。这3段对话设计的目的在于巩固学生所学的知识，并提供不同情景引导他们实际应用。教师可设计如下3幅简笔画。
教师可分段放录音或在课前事先安排3位学生与教师配合表演这3段对话。然后进行全班、半班或两人一组的练习。教师分段抽查数组表演情况。在学生已基本能分别表演3段对话的基础上，让他们将3段对话串在一起进行表演，教师可用简笔画或手势、动作来提示学生。
最后教师应鼓励学生实际应用所学知识，如让学生根据第69课的“instructions”，依照第72课的3段对话，自编对话，进行表演。以下4组对话包括了instructions中所有的注意事项，并尽量使用带情态动词的被动语态。例如：
1．A: Will you help me plant this tree, please?
B: Of course/Certainly. What do you want me to do?
A: Well, dig a hole large enough for the tree, But don't dig the hole too deep/the hole should not be too deep.
B: OK. I've dug a hole.
2．A: Good. That's done. Hold this stick While I knock it in.
B: OK. Make sure that it is straight.
A: Is it straight (now)?
B: More or less!
3．B: What's next?
A: Put the tree in the hole now/The tree must be put in the hole now.
B: OK. I've done that.
A: Right. I'll put the earth back in the hole again while you hold the tree straight.Then, let's push the earth down hard with our feet several times.
4．B: Good. Now the tree must be tied to the top of the stick to keep it straight.
A: OK. While you're doing that, I'll go and get some water.
B: OK. But can we go and have a drink after that?
A: A drink? We're only just started! There are twenty more trees to be planted.(Certainly. Let's go. But we have twenty more trees to be planted.)
（二）语法教学
本单元在前两个单元学习一般现在时和一般过去时的被动语态的基础上，继续学习带情态动词的被动语态。
在第69课，以显著的位置展示题为“HOW TO PLANT A TREE”的操作规程（instructions），教师如果仅仅是按部就班地讲解，就会使学生感到枯燥乏味。要充分利用课文中所提供的情景，在有意义的情景中教学语法知识。例如，教师可利用教师用书所提供的简笔画来引出新的语法知识。学生基本掌握instructions的大意后，教师应引导他们理解情态动词的用法。到了第71课可采用对比的方法。教师列出两个框框，要求学生分别填上课文中已出现的带情态动词的句子，和可以由主动语态变为带情态动词的被动语态的句子，把变化后的句子填入框内。如下表：
学生在做这个练习时，对本课句型与词汇有了进一步认识，同时也锻炼了写的能力。
在有条件的学校可放教学录相以加深印象。在全班读熟课文后，让学生独自准备几分钟，进行连锁练习，按次序复述instructions，也可两组之间进行比赛，由A组说出第一条注意事项，再由B组说出下一条。最初可完全复述课文原句。熟练后，可全部用主动语态或全部用被动语态，或一句主动语态一句被动语态交替出现，或句子中带有情态动词等方式进行操练。然后做练习册第69课练习1和3。第71课第二和三部分也是配合此项语法重点的教学而设计的。
neither…nor是本单元要求四会掌握的并列连词。而在本册第1课我们学习了both这个词。教师可通过both与neither…nor的相反语义来自然地呈现新句型。例如：教师出示图片或简笔画，引导学生用both和neither… nor造句。如：
再出示一幅图；造句如下：
这样分层次引入，就会使学生对neither…nor的用法有了更形象、清晰的认识。最后做第69课练习2。
本单元第70课教学了计量（measurement）表达法。具体的用法可参见教学参考资料。
教师可利用学生身边的事物教学计量表达法。例如描述教室及桌椅，可说出以下句子：
The classroom is 3.5 metres high, 4.5 metres wide and 5.5 metres long.
The table is half a metre high.
也可以出示一幅世界地图，让学生造句：
The Yellow River is 5,464 kilometres long and between… and… metres deep.
Mount Qomolongma is 8848.13 metres high.
The Yangtze River is about 6,300 kilometres long.
The lake is between 150 and 250 metres wide.
以上例句呈现完毕后，可让学生自己归纳计量表达法的特点，并将它写在黑板上：metre(s) /kilometres+long/ wide /deep /high /tall…
第71课第一部分和此课Wb.Ex 2是为练习计量表达法而设计的。教师还可要求学生造句，造句最多而错误最少的学生将给予奖励。
（三）阅读教学
在教学本单元阅读课文时，教师首先要让学生了解课文大意，然后帮助学生分段理解，并可划分段落，找出主题句(topic sentence)。在本课结束时，学生应能复述课文。
在阅读前，教师可设置如下问题，让学生猜测并讨论，以引起他们的阅读兴趣。
What's the Great Green wall?
Where does China build the Great Green Wall?
What does the Great Green Wall do?
在学生讨论过程中，教师可利用学生用书第Ⅳ页彩图和教师用书提供的材料（Notes），适当给学生们补充一些背景知识。
T: Sanbei shelter-forest（三北防护林）is known as China's “Great Green Wall”. It is a“Great Green Wall” of trees, millions of trees. China has built a new Great Green Wall across the northern part, including Inner Mongolia, Shanxi, Hebei, Beijing and Tianjin. The GreatGreen Wall also covers some of the Northwest (Xinjiang, Qinghai, Gansu, Ningxia and Shaanxi) and the western part of the Northeast (Liaoning, Jilin and Heilongjiang). It includes altogether 13 provinces, cities and autonomous regions（自治区）. Its total area is 4,069,000square kilometres, which cover 42.4％ of the land of China. The building of the Great GreenWall will take 73 years (1978-2050). The Great Green Wall has already saved a lot of land by stopping the wind from blowing the earth away and the sand from moving towards the rich farmland in the south. But more “Great Green Walls” are still needed and not only in China.They must be built all over the world.
教师在介绍背景知识时，可借助中国地图、手势等使学生大致了解，必要时可用汉语解释。文中划线句子为课文中原句或对原句稍加改动的句子。教师在讲到这些句子时可适当强调、重复，以加深学生的印象。
然后让学生打开书阅读课文。在确知大部分学生已基本掌握课文大意的情况下，要求他们划分课文段落并找出每个段落的主题句（topic sentence）或总结段落大意。课文的段落划分和主题句或大意如下：
第一段：第1自然段
王题句：… what has happened to the forests of the USA in the last 350 years.
主题句即大意
第二段：第2-3自然段
主题句：China does not want to copy the USA's examples.
大意： something about the Great Green Wall in China
第三段：第4-6自然段
主题句：
大意：something about Wang Feng, other workers and their work; what Wang Feng thinksabout the Great Green Wall and his work
教师还可以让学生填写下表：
提取主题词（key words）也有助于帮助学生复述课文大意。
练习册第70课练习1和3可用来配合课文的阅读教学。
《阅读训练》Unit 18提供了两篇阅读文章，第一篇共有285个词，留 5-6分钟让学生快速阅读。第二篇共有124个词，留2-3分钟阅读。
（四）笔头训练
本单元课文中没有专门设置写的练习。但在口语、语法和阅读教学中都贯穿着形式多样的笔头练习。练习册中也安排了许多笔头练习，如第69课练习1、2和3，第70课练习3和4；第71课练习1、2和3，第72课练习2和3。
教师可将练习册第71课练习3改编成一个要求学生仿照课文，写题为“How to plant vegetables in winter”操作程序的笔头练习。例如：
How to plant vegetables in winter
1．A greenhouse must be built first. It should be made neither of wood nor of earth. It must be made of glass.
2．Build a greenhouse large enough for the vegetables. A large greenhouse may be 10 metres long, 5 metres wide and 2.5 metres high.
3．Make sure that the sunshine can reach the vegetables through the glass. The wind and the cold air can be stopped from getting in.
4．The air inside the greenhouse should always be kept fresh.
教师可布置学生写一篇“How to plant flowers”的文章，使学生有机会运用所学知识来完成一项具体的任务。提示词：seeds, flower pot。
参考教案 Unit 18 Planting trees 教学参考资料 示例二
教学参考资料（Reference for teaching）
补充注释（Additional notes）
1．Come to school in your old clothes tomorrow!明天穿旧衣服上学。介词in在此表示“穿，戴”。又如：
The woman in red is his mother.穿红衣服的女人是他母亲。
2．Tree Planting Day植树节。
注意节日名称要大写。如Children's Day儿童节，Women's Day妇女节3．-neither too wet nor too dry.既不要太潮湿也不要太干燥。
neither…nor…是由两个含有否定意义的连词组成的词组，意思是“既不……也不……”。它的反义词组为“both…and…”。
使用这个词语时应注意两点：
1）注意连接两个平行结构
2）neither…nor…后面谓语动词的人称和数，要与离它最近的主语保持一致。例如：He is neither a worker nor a teacher.他既不是工人也不是教师。Neither Kate nor I am American.凯特和我都不是美国人。
4．Dig a hole large enough for the tree.给树挖一个足够大的坑。enough通常放在它所修饰的形容词之后。如：long enough足够大，old enough够年龄。
5．…as often as possible尽可能常……。
类似的用法还有as soon as possible尽可能地快；as far as possible尽可能地远些。
6．…about a third was…大约三分之一是……。
a third三分之一，还可以说one third。
分子是1以上的数字，分母用复数形式。如：two thirds三分之二
二分之一可用“one second, a second, half”表示。
7．Today, too many trees are still being cut down in the USA.今天在美国仍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形式，表示“正在被……”。又如：
The silk is being produced by the factory.这个工厂正在生产丝绸。
8．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，宽在400至1,700公里之间。
表示计量的方法是：数词+metres/ kilometres+ long/ wide/ deep/ high/ tall…表示重量可用数词+ kiloyrams+heavy。
The classroom is 4 metres wide.这个教室有4米宽。
The river is about 10 metres deep. 这条河大约有10米深。
9．This year alone…仅仅今年……。
alone在此是副词，用在名词或代词后面，表示“只，仅仅”。
10．There are twenty more trees to be planted!还有20棵树要种呢！
句中to be planted是动词不定式的被动式，作名词trees的定语。动词不定式作定语时，通常放在被修饰名词之后。又如：
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。
参考教案 Unit 18 Planting trees 教学步骤 示例二
教学步骤 (Teaching steps)
Lesson 69
Step 1 Revision
Check the homework. Briefly revise the comparison of adjectives and adverbs.
Step 2 Presentation
This is mainly a presentation of new vocabulary Draw or show a picture of a tree. Ask What's this?Tell the Ss Today we are going to learn how to plant a tree Translate plant a tree into Chinese and get the Ss to practise saying the word plant.
Say We need to dig a hole in the ground. Teach digby an action. Draw a picture showing a hole.Continue: Then we put the tree in the hole. (Gestures.)Repeat. Then get the Ss to tell you what to do. Whatdo I do first? What do I do next?
Write the new words and phrases (dig, put/knock…into, put the earth back, tie, water) on the Bb.
Step 3 Read and act
SB page 69, Part 1. Speech Cassette Lesson 69. AskWhat's happening tomorrow? When is Tree Planting Day? (March 12). Let the Ss read the dialoguesilently to find the answer. Play the tape for the Ss tolisten and repeat. Then let the Ss practise the dialoguein pairs.
Step 4 Read
SB page 69, Part 2. say Here are some instructions for planting a tree. Go through the first one with the whole class. Make sure they understand the meaning of just right and neither…nor =not too wet, not too dry, either. Note that it's warmer= it's warmer in spring than in winter. Answer the first two questions at the bottom of the page with the whole class, so they understand what to do. (Both are untrue.)
Let the Ss read the other instructions and answer the rest of the questions in pairs. Check the answers with the whole class.
True: 4,5,7. Untrue: 1,2,3,6.
Deal with any problems that arise: explain the meaning of Make sure. Note that it in instruction 3 refers to the stick and in instruction 4 it refers to thetree. Point out the use of so that to introduce a clause of result.
Step 5 Grammar focus
Remind the Ss of instructions using must and should.Draw this table on the Bb:
Get the Ss to make up true sentences using these boxes.
Step 6 Reading aloud
SB page 69, Part 2 Speech Cassette Lesson 69. Playthe tape for the Ss to listen and repeat Pay attention to the use of neither… nor, knock… into, must/should not and it.
Step 7 Workbook
Wb Lesson 69, Exx. 1-3.
Do Ex. 1 orally in class. Write down the missing words: 1 plant, shall, dig, get/carry, help; enough, right; 3 put, sure, earth.
For Ex. 2, go through the model and do the first sentence with the whole class, then let them work alone or in pairs. Check the answers with the whole class.
Do Ex. 3 orally with the whole class.
Step 8 Consolidation
Get the Ss to tell you how to plant a tree using the new vocabulary and structures that they have learnt inthis lesson.
Homework
Finish off the Workbook exercises.
Do Ex. 2 in the exercise books.
Revise the contents of this lesson.
参考教案 Unit 18 Planting trees 教学步骤 Lesson 70 示例二
Lesson 70
Note: “Sanbei shelter-forest”（三北防护林）is known as China's “Great Green Wall”. It stretches across the Northwest (Xinjiang, Qinghai, Gansu,Ningxia and Shaanxi), the western part of the Northeast (Liaoning, Jilin and Heilongjiang) and the northern part of North China (Inner Mongolia, Shanxi, Hebei, Beijing and Tianjin), including 13 provinces ,cities and autonomous regions. Its total area is 4,069,000 square kilometres, which covers 42.4％ of the land of China.
The building of the great Green Wall will take 73 years (1978-2050). It will change China's ecologic environment and help develop her agriculture, forestry, animal husbandry and commodity economy in the above-mentioned regions.
Step 1 Revision
1 Get the Ss to tell you how to plant a tree.
2 Revise should and must on the Bb, as in TB Lesson 69, Step 5.
3 Check the homework.
Step 2 Preparation for reading
Tell the Ss Today we are going to read about a Great Wall. No, not the Great Wall of China, but a great wall of trees. This is called the Great Green Wall.Draw a picture of a tree on the Bb. Ask What's this?Add more trees and teach the word forest. Draw a mountain covered in trees and say This forest is growing on a mountain.
SB page 70. Ask the Ss Why was the Great Green Wall built? Read the passage quickly to find the answer. (The answer is in the third paragraph.)
Step 3 Reading
Wb Lesson 70, Ex. 1. Read through the questions with the Ss and make sure they understand them. (Translate difficult parts into Chinese if necessary.)Get the Ss to read the passage more carefully. Then ask the Ss to work in pairs, answering the questions in Wb Ex. 1 orally. Check the answers with the whole class.
Deal briefly with any grammatical or lexical problems. Point out the compound words farmland: farm+ land, workplace: work+ place. Get the Ss to guess the meaning of new words or difficult phrases if possible.
Notes:
1）In 1850, about a third was covered by forests. a third = a third of the USA
2）leaving only sand = when the forests disappeared only sand remained
3）towards the rich farmland: towards = in the direction of (not to)
4）among the young trees: among is used for more than two things; between is used for two things
5）The more, the better: exactly the same as Chinese 越多越好，多多益善。
6）we hope to: hope + infinitive
7） pointed to: note the use of to in this phrasal verb.Point at is also possible.
You can also draw attention to the use to the Passive Voice in the passage. This structure will be covered later in the unit.
Step 4 Reading aloud
SB page 70. Speech Cassette Lesson 70 Play the tape for the Ss to listen and repeat as a class, in groups, in pairs or individually.
Step 5 Workbook
Wb Exx. 2-4.
Do Ex. 2 orally with the whole class. The answers are:1 d, 2 f, 3 b, 4 e, 5 a, 6 c.
Ex. 3 may also be done orally first, before the Ss write down the answers on their own.
The answers are: forests, land, sand, copy, more,more, across, long, wide, from, stop, towards, farmland, be.
The answers to Ex. 4 are; 1 A, 2 D, 3 C, 4 D.
Step 6 Consolidation
Revise the contents of the passage by asking the questions in Wb Ex. 1.
Homework
Finish off the Workbook exercises.
Revise the contents of the reading passage.
write down the answers to the questions in Ex. 1 in the exercise books.
参考教案 Unit 18 Planting trees 教学步骤 Lesson 71 示例二
Lesson 71
Step 1 Revision
1 Revise the contents of the reading passage in Lesson 70, using the questions in
Wb Lesson 70,Ex. 1 to guide you.
2 Check the homework.
Step 2 Presentation
Bring a ruler into class (try to borrow a metre ruler, if possible). Ask one or two Ss How tall are you?
Measure them against the Bb. Say He/ She is one metre… tall.
Then ask the whole class How long do you think the classroom is? Get them to guess, using I think it's…metres long. Measure the length to see who's right.Repeat for high and wide (desk /door /window etc).
Finally, write sentences on the Bb, like these:(Name) is one metre sixty tall.
The classroom is (eight) metres long.
The(door) is (two and a half) metres high.
Point out the position of the adjective at the end of the sentence.
Step 3 Practice
SB page 71, Part 1. Read through the phrases in the boxes and revise the meaning of any difficult words. Get individual S3 to make up true sentences.
Step 4 Presentation
Revise the instructions for planting trees, using should and must (not) +be +past participle.
Then tell the Ss that we can use the Passive Voice in the same way. Give some examples orally, using gestures:
A large hole should be dug.
A large stick must be knocked into the earth.
The tree should be tied to the stick.
The earth must be pushed down hard.
Get the Ss to do the gestures and repeat the sentences. Write the sentences on the Bb and point out the use of must/should + Passive Voice.
Help the Ss to change the sentences into the Active Voice and make sure they understand the difference between the Active and the Passive Voice. For example:
(active) We must push down the earth hard.
(passive) The earth must be pushed down hard.
The Passive voice is used when it is not necessary to mention the doer of the action.
Step 5 Read and say
SB page 71, Part 2 Get the Ss to make up sentences using the words in the boxes.
Step 6 Practice
SB page 71, Part 3. Do an example with the whole class, then let the Ss work in pairs, making up sentences in turn. Collect some examples from the whole class.
Step 7 Workbook
Wb Lesson 71, Exx. 1-3 For both these exercises, dosome examples orally with the whole class before theSs write down their answers. They can check their work in pairs before you collect the answers from the whole class The answers to Ex 2 are: 1 thick; 2 long,wide, wide; 3 deep, deep; 4 high/ tall, high/ tall;5 tall.
The answers to Ex. 3 are: be, made, long, wide,through, stopped, warm, more, all, in.
Homework
Finish off the Workbook exercises.
Revise the contents of this unit, particularly the of the Passive Voice.
Do Ex. 1 in the exercise books.
参考教案 Unit 18 Planting trees 教学步骤 Lesson 72 示例二
Lesson 72
Step 1 Revision
1 Check the homework.
2 Revise the measurement phrases in Lesson 71 by asking questions like these: How long is the Great Wall? How long is the Great Green Wall? How tall is (Name)? How wide is this window? etc.
Step 2 Preparation for listening
Tell the Ss Today we are going to hear about Tree Planting Day. What happens on Tree Planting Day?How do you plant a tree? etc.
Wb Lesson 72, Ex. 1 Read through the questions and make sure the Ss understand them. Get the Ss to read the dates and numbers aloud.
Step 3 Listening
SB page 72, Part 1.Listening Cassette Lesson 72.Wb Lesson 72, Ex. 1. Play the tape once or twice as necessary. Ss check their answers in pairs, then with the whole class Deal with any problems that arise.
Listening text
Listen to this passage, and choose the best answers in Wb Ex. 1:
Tree Planting Day was started in the year 1987. Every year, on March 12th., office workers, soldiers, workers, school children and old People go out to plant trees.
Last week, Class 3 went to plant some trees on Tree-Planting Day. Everybody was wearing old clothes. They met at the school, as usual, and then walked to a park about four kilometres from the school. They sang songs while they were walking. Miss Zhang and several other teachers went with them.
When they arrived at the park, they started work.A truck brought many young trees to the park. The children took them from the truck, and carried them to the right place. They worked together in pairs. They took turns to dig holes in the ground. It was hard work, but they enjoyed it. When the holes were deep enough, they put the young trees in the holes, and then filled them again. They pushed the earth down hard with their feet. Then they got water from a river, and watered the trees well. They also watered some of the older trees, too.
At the end of the day they were very happy. That day they planted over 250 trees.
“Well done!” said Miss Zhang. “You've done very Well today!”
The answers are: 1 A, 2 B, 3 A, 4 B, 5 C, 6 A.
Step 4 Read and act
SB page 72, Part 2. Speech Cassette Lesson 72.Present the dialogues one by one: you read both parts,then get the Ss to listen and repeat.
See if the Ss can guess the meaning of More or less!and That's done = That job is finished.
Next, get the Ss to practise the dialogue in pairs.Encourage the Ss to use gestures as they speak. See if they can remember the dialogues without the books! Ask some Ss to act out the dialogues.
Step 5 Checkpoint 18
Go through Checkpoint 18. Revise the formation of the Passive Voice with must/should /can/ may +be+ past participle. Get the Ss to say some rules for the class using this structure, e.g. English should bespoken in the English lesson.
Windows may be Opened when the weather is hot. Remind the Ss of the difference in meaning of must(obligatio), should (= ought to), can and may(possibility).
Make sure the Ss understand the meaning and use ofthe “useful expressions”.
Step 6 Test
Write these sentences on the Bb and ask the Ss to rewrite them in the Passive Voice.
1 You must not plant trees in very dry earth.
2 You should water trees often.
3 You may grow trees on a mountain.
4 You can dig a hole in the earth.
5 You can see the Great Green Wall in North China.
Step 7 Workbook
Wb Ex. 2. Let the Ss work in pairs first, then check the answers with the whole class. Finally, get the Ss to practise the dialogue in pairs. The answers are: 1 be grown, grown, be harvested, be harvested; 2 be dug, be dug, have finished, dig, be finished.
The answers to Ex. 3 are: be planted, be stopped, blowing, be stopped, moving, have, planted, be needed, see.
Homework
Finish off the Workbook exercises. Pay attention tothe Passive voice.
Study the contents of Checkpoint 18.