參考教案 教學建議
教學建議 (Suggested teaching notes)
一、教學內(nèi)容分析
本單元教學內(nèi)容主要圍繞“Planting trees”這個主題來展開。學生在已學習了一般現(xiàn)在時和一般過去時被動語態(tài)的基礎(chǔ)上，繼續(xù)學習含有情態(tài)動詞被動語態(tài)的構(gòu)成和用法，加深他們對被動語態(tài)的整體感知。同時學習一個新的語言點--計量 (Measurement) 的表達法。第69課通過一段對話來引入本單元主題“Planting trees”，然后提供了一篇有關(guān)種樹的注意事項。其中大部分句子含有帶情態(tài)動詞的被動語態(tài)，以此來引入本單元語法教學的重點。
第70課是一篇題為“THE GREAT GREEN WALL”的文章。學生們在閱讀、學習這篇文章后，對本單元的主題有了進一步的了解，繼續(xù)鞏固他們對帶情態(tài)動詞的被動語態(tài)的認識并開始學習計量的表達法。教師在教學本課時，應注意讓學生整體把握課文大意，同時教給他們一些閱讀技巧。
第71課由三段句型操練組成，旨在鞏固學生的語法和詞匯知識，讓他們能夠熟練運用這些知識。
第72課的聽力材料和三段對話也是圍繞植樹的主題設(shè)計和編排的，為教師和學生提供了進一步操練和交際運用的素材。本單元的語言重點通過復習要點作了總結(jié)。
二、教學方法建議
（一）口語教學
本單元第69課以Read and act的形式來引出本課的教學重點。教師應充分利用這個對話情景，進行對話表演，以提高學生的興趣，達到自然地呈現(xiàn)新課的目的。
教師在上課時，可穿一件舊衣服或工作服，問學生，“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?”這時，學生們可以進行多種猜測。在學生情緒高漲時，教師讓他們帶著問題聽課文錄音。在聽第一遍錄音后，利用本課掛圖，再讓學生聽一至兩遍錄音。為了幫助他們更好地理解對話的內(nèi)容和句型，教師此時可將一些關(guān)鍵詞寫在黑板上，如：in old clothes, What's happening? TreePlanting Day, Really? Wonderful!在學生了解了對話的基本內(nèi)容后，教師可放錄音讓全班跟讀或分角色對話。然后兩人一組借助黑板上的關(guān)鍵詞來復述或表演。注意這段對話的主要目的是引出下面的“instructions”，而且對話中新的語言知識不多，所以不必占用過多的時間。
第72課在Read and act下也有3段對話。但與第69課對話不同。這時學生已學完本單元的語法重點和閱讀文章。這3段對話設(shè)計的目的在于鞏固學生所學的知識，并提供不同情景引導他們實際應用。教師可設(shè)計如下3幅簡筆畫。
教師可分段放錄音或在課前事先安排3位學生與教師配合表演這3段對話。然后進行全班、半班或兩人一組的練習。教師分段抽查數(shù)組表演情況。在學生已基本能分別表演3段對話的基礎(chǔ)上，讓他們將3段對話串在一起進行表演，教師可用簡筆畫或手勢、動作來提示學生。
最后教師應鼓勵學生實際應用所學知識，如讓學生根據(jù)第69課的“instructions”，依照第72課的3段對話，自編對話，進行表演。以下4組對話包括了instructions中所有的注意事項，并盡量使用帶情態(tài)動詞的被動語態(tài)。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）語法教學
本單元在前兩個單元學習一般現(xiàn)在時和一般過去時的被動語態(tài)的基礎(chǔ)上，繼續(xù)學習帶情態(tài)動詞的被動語態(tài)。
在第69課，以顯著的位置展示題為“HOW TO PLANT A TREE”的操作規(guī)程（instructions），教師如果僅僅是按部就班地講解，就會使學生感到枯燥乏味。要充分利用課文中所提供的情景，在有意義的情景中教學語法知識。例如，教師可利用教師用書所提供的簡筆畫來引出新的語法知識。學生基本掌握instructions的大意后，教師應引導他們理解情態(tài)動詞的用法。到了第71課可采用對比的方法。教師列出兩個框框，要求學生分別填上課文中已出現(xiàn)的帶情態(tài)動詞的句子，和可以由主動語態(tài)變?yōu)閹閼B(tài)動詞的被動語態(tài)的句子，把變化后的句子填入框內(nèi)。如下表：
學生在做這個練習時，對本課句型與詞匯有了進一步認識，同時也鍛煉了寫的能力。
在有條件的學校可放教學錄相以加深印象。在全班讀熟課文后，讓學生獨自準備幾分鐘，進行連鎖練習，按次序復述instructions，也可兩組之間進行比賽，由A組說出第一條注意事項，再由B組說出下一條。最初可完全復述課文原句。熟練后，可全部用主動語態(tài)或全部用被動語態(tài)，或一句主動語態(tài)一句被動語態(tài)交替出現(xiàn)，或句子中帶有情態(tài)動詞等方式進行操練。然后做練習冊第69課練習1和3。第71課第二和三部分也是配合此項語法重點的教學而設(shè)計的。
neither…nor是本單元要求四會掌握的并列連詞。而在本冊第1課我們學習了both這個詞。教師可通過both與neither…nor的相反語義來自然地呈現(xiàn)新句型。例如：教師出示圖片或簡筆畫，引導學生用both和neither… nor造句。如：
再出示一幅圖；造句如下：
這樣分層次引入，就會使學生對neither…nor的用法有了更形象、清晰的認識。最后做第69課練習2。
本單元第70課教學了計量（measurement）表達法。具體的用法可參見教學參考資料。
教師可利用學生身邊的事物教學計量表達法。例如描述教室及桌椅，可說出以下句子：
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圖，讓學生造句：
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.
以上例句呈現(xiàn)完畢后，可讓學生自己歸納計量表達法的特點，并將它寫在黑板上：metre(s) /kilometres+long/ wide /deep /high /tall…
第71課第一部分和此課Wb.Ex 2是為練習計量表達法而設(shè)計的。教師還可要求學生造句，造句最多而錯誤最少的學生將給予獎勵。
（三）閱讀教學
在教學本單元閱讀課文時，教師首先要讓學生了解課文大意，然后幫助學生分段理解，并可劃分段落，找出主題句(topic sentence)。在本課結(jié)束時，學生應能復述課文。
在閱讀前，教師可設(shè)置如下問題，讓學生猜測并討論，以引起他們的閱讀興趣。
What's the Great Green wall?
Where does China build the Great Green Wall?
What does the Great Green Wall do?
在學生討論過程中，教師可利用學生用書第Ⅳ頁彩圖和教師用書提供的材料（Notes），適當給學生們補充一些背景知識。
T: Sanbei shelter-forest（三北防護林）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（自治區(qū)）. 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.
教師在介紹背景知識時，可借助中國地圖、手勢等使學生大致了解，必要時可用漢語解釋。文中劃線句子為課文中原句或?qū)υ渖约痈膭拥木渥印＝處熢谥v到這些句子時可適當強調(diào)、重復，以加深學生的印象。
然后讓學生打開書閱讀課文。在確知大部分學生已基本掌握課文大意的情況下，要求他們劃分課文段落并找出每個段落的主題句（topic sentence）或總結(jié)段落大意。課文的段落劃分和主題句或大意如下：
第一段：第1自然段
王題句：… what has happened to the forests of the USA in the last 350 years.
主題句即大意
第二段：第2-3自然段
主題句：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
主題句：
大意：something about Wang Feng, other workers and their work; what Wang Feng thinksabout the Great Green Wall and his work
教師還可以讓學生填寫下表：
提取主題詞（key words）也有助于幫助學生復述課文大意。
練習冊第70課練習1和3可用來配合課文的閱讀教學。
《閱讀訓練》Unit 18提供了兩篇閱讀文章，第一篇共有285個詞，留 5-6分鐘讓學生快速閱讀。第二篇共有124個詞，留2-3分鐘閱讀。
（四）筆頭訓練
本單元課文中沒有專門設(shè)置寫的練習。但在口語、語法和閱讀教學中都貫穿著形式多樣的筆頭練習。練習冊中也安排了許多筆頭練習，如第69課練習1、2和3，第70課練習3和4；第71課練習1、2和3，第72課練習2和3。
教師可將練習冊第71課練習3改編成一個要求學生仿照課文，寫題為“How to plant vegetables in winter”操作程序的筆頭練習。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.
教師可布置學生寫一篇“How to plant flowers”的文章，使學生有機會運用所學知識來完成一項具體的任務。提示詞：seeds, flower pot。
參考教案 Unit 18 Planting trees 教學參考資料 示例二
教學參考資料（Reference for teaching）
補充注釋（Additional notes）
1．Come to school in your old clothes tomorrow!明天穿舊衣服上學。介詞in在此表示“穿，戴”。又如：
The woman in red is his mother.穿紅衣服的女人是他母親。
2．Tree Planting Day植樹節(jié)。
注意節(jié)日名稱要大寫。如Children's Day兒童節(jié)，Women's Day婦女節(jié)3．-neither too wet nor too dry.既不要太潮濕也不要太干燥。
neither…nor…是由兩個含有否定意義的連詞組成的詞組，意思是“既不……也不……”。它的反義詞組為“both…and…”。
使用這個詞語時應注意兩點：
1）注意連接兩個平行結(jié)構(gòu)
2）neither…nor…后面謂語動詞的人稱和數(shù)，要與離它最近的主語保持一致。例如：He is neither a worker nor a teacher.他既不是工人也不是教師。Neither Kate nor I am American.凱特和我都不是美國人。
4．Dig a hole large enough for the tree.給樹挖一個足夠大的坑。enough通常放在它所修飾的形容詞之后。如：long enough足夠大，old enough夠年齡。
5．…as often as possible盡可能常……。
類似的用法還有as soon as possible盡可能地快；as far as possible盡可能地遠些。
6．…about a third was…大約三分之一是……。
a third三分之一，還可以說one third。
分子是1以上的數(shù)字，分母用復數(shù)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.今天在美國仍有大量樹木繼續(xù)被砍伐。
be+being+過去分詞是現(xiàn)在進行時的被動語態(tài)形式，表示“正在被……”。又如：
The silk is being produced by the factory.這個工廠正在生產(chǎn)絲綢。
8．The Great Green Wall is 7,000 kilometres long, and between 400 and 1,700 kilometres wide.這綠色長城長為7,000公里，寬在400至1,700公里之間。
表示計量的方法是：數(shù)詞+metres/ kilometres+ long/ wide/ deep/ high/ tall…表示重量可用數(shù)詞+ kiloyrams+heavy。
The classroom is 4 metres wide.這個教室有4米寬。
The river is about 10 metres deep. 這條河大約有10米深。
9．This year alone…僅僅今年……。
alone在此是副詞，用在名詞或代詞后面，表示“只，僅僅”。
10．There are twenty more trees to be planted!還有20棵樹要種呢！
句中to be planted是動詞不定式的被動式，作名詞trees的定語。動詞不定式作定語時，通常放在被修飾名詞之后。又如：
We have a lot of food to eat. 我們有許多食物可吃。
I have many books to read.我有許多書要看。
參考教案 Unit 18 Planting trees 教學步驟 示例二
教學步驟 (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.
參考教案 Unit 18 Planting trees 教學步驟 Lesson 70 示例二
Lesson 70
Note: “Sanbei shelter-forest”（三北防護林）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.
參考教案 Unit 18 Planting trees 教學步驟 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.
參考教案 Unit 18 Planting trees 教學步驟 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.