Unit2 Working the land-Writing
Speaking
The farmer is persuading the customer to buy his/her “green food”. You need to … The advantages are… I’d prefer …bof … Should I/we...?
◎Writing Task on Page 53.
Sample writing:
1600 years ago the Chinese writer Jia Sixie wrote a book Qi Min Yao Shu about good agricultural practices. Today some of Jia Sixie’s ideas are still very useful to our modern times, but we have some problems today that he never had in his time.
Although our modern farmers still use some of Jia Sixie’s ideas today, they face problems that were never heard of in Jia Sixie’s day.
F: Well, let me explain. I’d rather feed my family on green food than other vegetables because they are grown without chemical fertilizers. C: But the price is too expensive! I’d prefer to buy good food if I can afford it.
F: This is good value for money because you’ll have healthier children. They won’t have to take time off work. In the long run you’ll be benefit. C: Certainly I’d like to buy what is safe and healthy. Perhaps I’ll try some of your vegetables and if they are as good as you say, I’ll be back next week!
However, we have some problems today that Jia Sixie never faced in his time. We have environmental pollution that harms fields and crops. We have great competition in the marketplace. We have new, dangerous and powerful crop diseases.
Some of Jia Sixie’s ideas are still very useful to our modern times. Farmer still clear their fields of weeds. They still plough deeply the first time and less deeply the second time. In addition, farmers everywhere still understand that changing crops in the fields is still important.
Sample dialogue: F= Farmer C= Customer
F: Good morning! Would you like some organic carrots this morning? C: Hmm… They’re a little expensive! What is the advantage of …？ ？
F: The advantage of these vegetables is that they are green food so they’re safe to eat and good for your family. C: But what’s the advantage of having green food? I know all vegetables are good for you and those down the road look green too. And I can buy them at half the price there.
It’s better of… It’s more expensive but… I don’t like… because… I’d rather… This is good value because… You’ll taste the difference when… If I have a choice I’ll choose… It’s a great pity that…
21版：(创新设计) Unit 2 Working the land
Unit 2Working the landⅠ.阅读理解A(2020·唐山质量检测)The UK’s Best Theme ParksDrayton Manor Theme Park，StaffordshireThe new Tamarin Trail takes adventurers through beautiful gardens，allowing kids and adults to come face-to-face with a troop of monkeys.The park is also home to Europe’s only Thomas Land，which last year underwent a ￡2.5m expansion，including new rides.There are thrilling rides，including the stand-up roller coaster，Shockwave，and the 54-metre drop tower，Apocalypse.Adults from ￡15，children from ￡10(under-2s free).Thorpe Park，SurreyAll aboard Derren Brown’s Ghost Train which opened in July 2016.This 10-15 minute train journey includes exciting live-action performances，4D special effects and so on.Also new is“I’m a Celebrity...Maze(迷宫)”，and there are some of the highest and fastest rides in Europe here too.Adults from ￡28，children from ￡24(under-3s free).Warwick Castle，WarwickshireAlthough not officially a theme park，this medieval castle offers history，magic，myth and adventure to suit all ages，and is now home to the UK’s first fully interactive and multi-sensory Horrible Histories Maze，giving visitors a fascinating experience of getting lost in time.Form July，you can sleep over in the new riverside Middle Ages-themed woodland cottages of Knight’s Village.From ￡31(under-3s free).Chessington World of Adventures，SurreyFollowing the Pandamonium live show in 2016，last year saw The Gruffalo River RideAdventure open at Chessington，which has over 40 rides and attractions.Rides include Dragon Falls，Safari Skyway，Toadies Crazy Cars and Runaway Train.From ￡29(under-3s free).【语篇解读】本文是一篇应用文。
高中英语-M4_Unit_2_Working_the_land单元复习案例分析与反思AqAAMK
M4 Unit 2 Working the land单元复习案例分析与反思吴炫露一．教学目标1. 知识和技能目标能够掌握下列单元重点词汇的用法，并运用这些词汇来描述农业生产和农民的生活：thanks to, rid…of, build up, keep…free from, struggle, would rather, lead 2. 情感态度目标通过学习，了解农耕的辛苦和产生对农民的敬意。
回顾袁隆平的生平事迹，感受他所做的伟大贡献。
四．教学过程1. Enjoy the poemFarmers weeding at noon,Sweat down the field soon.Who knows food on a tray（盘）,Thanks to their hard work.T:What’s the title of the poem?Ss:悯农T: How do you feel about farmers?Ss: hard-workingthanks to的用法thanks to= because of= due to= owing to=as a result of= on account of 由于翻译：多亏了你帮忙，我才及时到达车站.Thanks to your help, I was able to arrive at the station in time.幸亏你，我才没淹死。
(save…from..)Thanks to you, I was saved from drowning.2. Talk about Dr. YuanT: What’s this?Ss: super hybrid riceT: Who’s the father of super hybrid rice?Ss: Yuan LongpingT: What kind of person do you think he is?Dr Yuan _______ a simple life. He _____ ______ work on the farm than have a rest. He has ________ for five decades to search for a way to increase rice harvest without _________(扩大) the area of fields. _______ to the discovery of super hybrid rice, his dream of ______ China of hunger is realized . He ______most of his time to increasing rice______(产量).Now, he has another dream---to _______(输出)his rice so that it can be grown all over the world.Keys: leads, would rather(…than…), struggled, expanding, Thanks, ridding(…of…), devotes(…to…), output, exportstruggle的用法struggle to do sth努力做某事struggle for sthstruggle against sthShe _________ to keep back the tears.(努力忍住泪水)Most animals have to struggle _____ existence in a dangerous world.rid的用法rid sb of sth. 使某人摆脱某物get/be rid of sth翻译：1）.She is trying to rid herself of dependence on drugs.(使自己摆脱对毒品的依赖) = She is trying to get rid of dependence on drugs2）. 你应该摆脱坏习惯You should rid yourself of bad habits.= You should get rid of bad habits拓展：rid sb of sth remind sb of sth accuse sb of sthinform sb of sth warn sb of sththe UN is trying to ___ the world __ hunger.His father was _______ taking bribes.受贿Thanks for your gift—it will always ____ me ____ you.3.talk about organic food and organic farmingT: Look at the pictures. These fruits look very delicious. Can you guess what kind of food it is?Ss: Organic food.T: What's the features of organic foodFeatures(特点) of organic food_______o f p o l l u t i o n_______n u t r i t i o nd o_______t o pe o p l e’s h e a l t h a n d t h e e___________Keys: free, rich in, good, environmentListen to the tape and fill in the blanksOrganic farming is simply farming without using_________. They _______ keeping their soil rich and ______ of disease.A healthy soil _______ disease and helps crops grow strong and healthy.Organic farmers often prefer using ______ waste from animals as fertilizer. They feel that this makes the soil in their fields _____ in minerals and so more fertile.This also keeps the air, water and crops ______ chemicals.Keys: chemicals, focus on, free, reduces, natural, rich, free from4.Words practicingexpand , export, satisfy, struggle, rid ... of, would rather, lead ... a life, thanks to, lead to, build up, keep….free from1）.With the development of science and technology China is _________ many kinds of electric products to developing countries.2）._________ a lot of hard work, it was a great success.3）. A child’s vocabulary ________ through reading .4）. Eating too much sugar can _____ health problems.5）. I’m very tired. I ______________ have a good sleep than go to the cinema. 6）.The swimmer ________________ （与…搏斗）the tide（潮水）.7）.In the past, farmers would let the animals do the work to ______ the fields _______ weeds.8）. All the pressure _________ and he was off work for weeks with stress.Keys: exporting, Thanks to, expands, lead to, would rather, struggled against, keep... free from, built up.build up的用法All the pressure built up and he was off work for weeks with stress."build up" in the sentence above has the same meaning with _________. B积聚，增加A. She has built up a very successful business. 创办，建立B. These chemicals in the food su pply build up in people’s bodies over time.C. You need more nutrition to build you up. 强健5.Consolidation中国的农民曾经过着很艰苦的生活，并一直受着饥饿的困扰。
新人教版 Book 4 Unit 2 Working the Land 课文
Unit 2 Working the landPart I a Pioneer for all PeopleAlthough he is one of China’s most famous scientists, Yuan Longping consider s himself a farmer, for he works the land to do his research. Indeed, his sunburnt face and arms and his slim, strong body are just like those of millions of Chinese farmers, for whom he has struggle d for the past five decade s. Dr Yuan Longping grows what is called super hybrid rice. In 1974, he became the first agricultural pioneer in the world to grow rice that has a high output. This special strain of rice makes it possible to produce one-third more of the crop in the same field s. Now more than 60% of the rice produced in China each year is from this hybrid strain.Born in 1930, Dr Yuan graduate d from Southwest Agricultural College in 1953. Since then, finding ways to grow more rice has been his life goal. As a young man, he saw the great need for increasing the rice output. At that time, hunger was a disturbing problem in many parts of the countryside. Dr Yuan search ed for a way to increase rice harvest s without expand ing the area of the fields. In 1950, Chinese farmers could produce only fifty million tons of rice. In a recent harvest, however, nearly two hundred million tons of rice was produce d. These increased harvests mean that 22% of the world’s people are fed from just 7% of the farmland in China. Dr Yuan is now circulating his knowledge in India, Vietnam and many other less developed countries to increase their rice harvests. Thanks to his research, the UN has more tool s in the battle to rid the world of hunger. Using his hybrid rice, farmers are producing harvests twice as large as before.Dr Yuan is quite satisfied with his life. However, he doesn’t care about being famous. He feel s it gives him less freedom to do his research. He would much rather keep time for his hobbies. He enjoy s listening to violin music, playing mah-jong, swimming and reading. Spend ing money on himself or lead ing a comfortable life also means very little to him. Indeed, he believe s that a person with too much money has more rather than fewer trouble s. He therefore gives millions of yuan to equip others for their research in agriculture.Just dream ing for things, however, cost s nothing. Long ago Dr yuan had a dream about rice plants as tall as sorghum. Each ear of rice was as big as an ear of corn and each grain of rice was as huge as a peanut. Dr Yuan awoke from his dream with the hope of producing a kind of rice that could feed more people. Now, many years later, Dr Yuan has another dream: to export his rice so that it can be grown around the globe. One dream is not always enough, especially for a person who loves and cares for his people.Part II Chemical or Organic Farming?Over the past half century, using chemical fertilizers has become very common in farming. Many farmers welcome d them as a great way to stop crop disease and increase production. Recently, however, scientists have been finding that long-term use of these fertilizers can cause damage to the land and, even more dangerous, to people’s health.What are some of the problems caused by chemical fertilizers? First, they damage the land by kill ing the helpful bacteria and pests as well as the harmful ones. Chemicals also stay in the ground and underground water for a long time. This affect s crops and, therefore, animals and humans, since chemicals get inside the crops and cannot just be wash ed off. These chemicals in the food supply build up in people’s bodies over time. Many of these chemicals can lead to cancer or other illnesses. In addition, fruit, vegetable s and other food grown with chemical fertilizers usually grow too fast to be full of much nutrition. They may look beautiful, but inside there is usually more water than vitamin s and mineral s.With these discover ies, some farmers and many customer s are beginning to turn to organic farming. Organic farming is simply farming without using any chemicals. They focus on keeping their soil rich and free of disease. A healthy soil reduce s disease and helps crops grow strong and healthy. Organic farmers, therefore, often prefer using natural waste from animals as fertilizer. They feel that this makes the soil in their fields richer in minerals and so more fertile. This also keeps the air, soil, water and crops free from chemicals.Organic farmers also use many other method s to keep the soil fertile. They often change the kind of crop in each field every few years, for example, growing corn or wheat and then the next year peas or soybeans. Crops such as peas or soybeans put important mineral s back into the soil, making it ready for crops such as wheat or corn that need rich and fertile soil. Organic farmers also plant crops to use different level s of soil, for example, planting peanuts that use the ground’s surface followed by vegetables that put down deep root s. Some organic farmers prefer planting grass between crops to prevent wind or water from carry ing away the soil, and then leaving it in the ground to become a natural fertilizer for the next year’s crop. These many different organic farming methods have the same goal: to grow good food and avoid damaging the environment or people’s health.。
高中英语真题-Unit2 workingtheland_5
高中英语真题:Unit2 workingtheland诵读积累古话说：民以食为天。
目前，不少地方土地干旱，粮食短缺问题依然是急需解决的问题。
请以Food Shortage为题，写一篇120个词左右的英语短文。
要求：1.介绍现在的饥荒状况2.说明其原因3.应当采取的措施Food ShortageAs we know，food shortage has hit many countries and even caused social unrest in some areas. But what has caused the current world f ood crisis？Firstly，annual world grain output had declined because of climate ch anges. Secondly，lots of farmland has given way to factories and buildings due t o the rapid development of industry and urbanization. Besides ，faced with the rising energy prices，some people use grain for biofuel(生物燃料)，which has worsened the severe situation.How can we deal with the problem？On the one hand，we should focus on the environmental protection and improve the ecology. On the other hand，strict measures should be taken to protect farmland.If the whole world works together，I think more food will be produced and we can create a harmo nious world.单元知识必备核心考点： focus 3年2考 if so 3年1考1．struggle vt. 搏斗；斗争；努力；挣扎n．斗争；挣扎struggle with/against 与……搏斗/斗争struggle for sth./to do sth. 努力/争取……struggle to one‘s feet 挣扎着站起来with a struggle 费劲地1).They had to struggle for their lives against/with weather and wild animals.为了生存他们必须与天气和野兽抗争。
unit-2-working-the-land-writing
Behind that healthy smile, there is our green food!
健康笑容来自我们的绿色食品！
Making a good life for you!
为你创造更美好的生活！
Take time, any time!
无论何时，享受生活！ Once tasted, always loved!
Second, it is the use of clean water irrigation, does not contain other harmful substances.
Third, it is from an excellent ecological(生态的) environment, maintain good health, is an important step towards healthy state.
……
Imagine that a green food shop will be set up near our school, and the owner invites you to design a poster for advertising green food in her shop. How would you design this poster?
The Symbol of Green Food
What is the advantagesБайду номын сангаасof green food?
First of all, green food does not use chemical fertilizers, environmental protection, in the production process without toxic, more natural than ordinary food more healthy.
人教版高中英语必修四课件：Unit-2-Working-the-land-Words-and-exp
regrettable adj 可惜的；令人遗憾的
10.build up 逐渐增强;建立;开发
1) Try and build up confidence a bit . 试试让他增进自信。 2) Good food builds up the body. 好的食物使身体更加强壮。 3) She’s built up a very successful business. 她创办的生意很红火。
近义词组:be content with 同根词:satisfy vt. 满足;使满意;
satisfaction n. 满意；满足 be satisfied to do对做……感到满意。如：
2) He was satisfied to win the race. 他对赢得赛跑感到满意。
6.would rather 宁愿，宁可
与…斗争，为反对…而斗争， struggle for 为争取…而斗争
2.expand vt＆vi 使变大；伸展
1) Metals expand when heated. 金属受热则膨胀。 2) The sofa expands to form a bed . 沙发展开形成一张床。
搭配：expand …into 把…扩展/膨胀为… His studio was expanded into a big firm. 他的工作室扩大规模而成为一家大公司了。 拓展：expansion n 扩大；扩张；扩展
7.therefore adv. 因此;所以;因而
1) we don’t have enough money and therefore we
人教版高中英语必修4 Unit 2 Working the Land - Writing
人教版高中英语必修4 Unit 2 Working the Land -WritingLesson plan for NSEFC IV Unit 2 Working the LandWriting一、Background information:, Students: Senior high school, Grade 1, Lesson duration: 45 minutes二、Teaching objectives:By the end of this lesson, students should be able to:, Know the major types and features of posters after searching posters on theInternet, Know the basic contents of posters after concluding some posters in theteacher’s blog, Make a poster for advertising, Evaluate a poster三、Teaching contents:, The major types of posters, The major features of advertising posters, The basic contents of advertising posters, How to design a poster for advertising四、Teaching aids:Video，PPT, Mindjet MindManager 8, E-mail, Blog,五、Type of the lesson: Writing lesson for senior school students六、Teaching procedures:Step 1: Greeting and leading in ( 3 minutes), Greeting and warm up: Show a clip of advertising video about green food (30seconds).Ask students the advantages of green food, Create a situation for the whole class: Tell the students they may have achance to enjoy free green food grew in organic farm. Then play a one-minute video from a green food producer who wants to set up a greenfood shop near our school. The producer invites students to design a posterfor advertising green food in her company’s poster designing competition.All the contestants could enjoy some free green food. The winner can have abig surprise., Encourage students to take part in this competition.Step 2: Instruct the students to find out major types of posters and todecide which kind to follow (3 minutes) , Transient point: Some of you said that you don’t know how to design a poster.Take it easy. Because we will learn how to do it together. First of all, let’ssearch some poster on the internet and see how many types of posters thereare (specific websites are provided here), Provide a website of posters to students and give them 2 minutesto classifyposters (political posters, advertising posters, event posters, educationalposters, art posters, etc.)., Ask students which type of poster we can follow in designing a green foodposter for advertising (advertising poster).Step 3: Instruct the students to find out features of advertising posters(5 minutes), Transient point: Most of the advertising posters are so attractive. If we wantto make our poster more successful, we must learn how they could be attractive. So let’s have a discussion and find the secret., Give students 3 minutes to discuss how advertising posters couldbeattractive in groups. Ask some of the students to present their conclusion., Conclude students’ presentation and add more features about a advertisingposter if necessary (persuasive reasons, concise expression, attractiveadvertising pictures, etc.).Step 4: Instruct the students to find out the basic contents of advertising posters (8 minutes) , Transient point: In order to make a complete poster, we need to learn moreabout its conte nts. Now, let’s look at some posters and find out their majorcontents., Give students 5 minutes to analyze some advertising posters on the teacher’sblog and find out their basic content in group discussion (main heading,explanation of promoting, reasons of buying, address, time etc.).Ask one ortwo group to present their findings., Use a mind-map to review what we have learned about posters.Step 5: Finish advertising poster writing in group (20minutes), Transient point: Since we have learned some features and the basic contentsand of advertising posters, I think we have a clearer idea about advertisingposter. Now, let’s start to write our own poster., Ask students to form groups of four and work together to write a poster(focus on explanation of promoting, reasons of buying) in 15 minutes. Thenthey publish the first draft in the blog., Make comment on one or two of the students’ works and correctthem inorder to make them more concise., Ask students to correct their own writing again or give suggestion to othersby leaving message after one’s message.Step 6: Instruct students to design a complete poster including both textual and graphic elements (6 minutes), Transient point: Well, you’ve done a good job on writing a poster. But aposter is not just some words, right? Now, let me show you a sample madeby Word and we could learn how to make a beautiful poster together., Show students a poster made by Word. Teach them how to use samples tomake a new poster., Provide students several samples and pictures. Give students 3 minutes tomake new ones by replacing words and pictures. Ask them send their worksto the teacher’s mailbox. Show one of the works and make a brief comment. , Ask students to polish their advertising posters for green food and e-mailthem to the teacher’s mailbox in the weekends. Then publish them on theclass blog.七、Homework, Ask students to polish their advertising posters for green food and e-mailthem to the teacher’s mailbox in the weekend s. , Ask all the students to vote for their favorite posters next week.八、Reflection (to be written after class)。
高中英语必修四《unit2 Working The Land 》全英文说课稿
《unit2 Working The Land 》示范说课稿Unit 2 Working The Land (NSEFC B4)Reading: A Pioneer For All PeopleA teaching plan interpretationTarget students: students of average level in Senior 2Period under interpretation: The second period of Unit 2 Working the LandTime: 2nd, Dec, 2008Teaching material: Reading passage A pioneer for all peopleTeaching aids: A multi-media set for teaching, a tape recorder, a power-point display works Teaching aims:a) Knowledge-oriented aims: Some idiomatic phrases and complicated sentences.b) Ability-oriented aims: Comprehension of Dr. Yuan’s work and life.c) Moral-oriented aims: Analyze Dr. Yuan’s characteristics and personality traits.Teaching principles:a)student-centered and teacher-directedb)task-based learning and purpose-focused teachingc)the communicative language teaching approachTeaching methods:a)free talkb)question and answer activityc)group presentationd)pair worke)role-playDifficult teaching point:Help students how to conclude Dr Yuan’s personality through the descriptions about his appearance, achievements and dreams.Important teaching points:Encourage students to be ambitious like Dr Yuan and follow his steps to make contributions.Exploring work before class:•New words & expressions•Assigned the students to surf on the Internet to find out some information about Chinese agriculture and Yuan Longping.Aims: 1. Remove the language obstacles before class and develop students’ habit of self-study.2. Gain some background information about Yuan Longping.Teaching procedures:Step 1: Lead-in (2m’)Show pictures of hungry Africans and draw out Dr. Yuan.Aim: To grab students’ attention and lead in the topic of the passage.Step 2: Task-based reading (7m’+ 5m’+8m’)1. First reading (group work and discussion) (7m’)The students will be given 7 minutes to skim for:1) the main idea of the whole passage (4m’)2) the main idea of each paragraph (3m’)Aim:To enable students to get a general idea and the organization of the passage.2. Second reading (individual work and chart filling) (5m’)Students will be divided into 4 groups to finish 4 different tasks. This time more detailed information is called for. After the reading, there will be different tasks for different groups. Group 1: Dr Yuan’s appearance and Dr Yuan’s achievementGroup 2: Dr Yuan’s biographyGroup 3: Dr Yuan’s personalityGroup 4: Dr Yuan’s dreamsAim: This task is aimed to develop students’ ability of reading for useful information within a limited time. Meanwhile, the teacher can help to remove the language obstacles in the reading passage.3. Dig-in reading (pair work and personality recognition) (8m’)How do you like Dr. Yuan? What characters can you conclude from these sentences?Try to summarize Dr. Yuan’s characteristics.Aim: To enable students to get a deeper understanding of Dr. Yuan and appreciate his noble personality.Step 3: Movie watching (3m’)A 3-minute short movie about Dr. Yuan will be played in order that the whole class may know him better.Aim: To know Dr. Yuan better in a vivid way.Step 4: An interview (pair work and role-play) (5m’+5m’)Suppose Dr. Yuan will visit our school and he will answer the questions after a speech.Prepare some questions, which may cover his life, agricultural research work, even his hobbies or love story and then show your interview.Aim:1. The interview focuses on teamwork, cooperation and collaboration.2. The purpose is to develop the students’ random thinking skills and practice their oral English.Step 5: Feedback (number game) (4m’)The students will play a number game--- What’s your lucky number? There are nine numbers to choose from and each number represents a different task. The task is mainly about the words, phrases and comprehension of the passage.Aim:To check the teaching effect and consolidate students’ basic knowledge about words and sentences.Step 6: Self assessment and assignment (1m’)Check out how much you have learned in class!Write an article which is entitled Dr. Yuan in my eyes.Aim: 1.To expand the information and to broaden students’ minds.2.To consolidate the knowledge and help improve students’ writing.。
Unit2 《Working the land》(新人教必修4)
ks5u精品课件
Task 3 Careful reading
Para. 1 Dr Yuan’s appearance and his achievement
Q1: What does Dr Yuan look like?
?
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In the late 1990s, Brown, an American scholar, came up with the theory of Chinese Menace(威胁), which said that in the 2030s, Chinese population will add up to 1.6 billion, and had the question who would feed the large population in China as well as in the world.
ks5u精品课件
Para4
What does “Wishing for things, however, costs nothing.” mean?
Dreams are free and everybody
can have ideas about
what they would like their future life to be.
ks5u精品课件
facts about Yuan’s super hybrid can produce 1/3 more of the crop in rice
capacity the same fields; more than 60%of the rice in China from this hybrid strain (能力) besides China, knowledge being Applica- circulated in India, Vietnam and other less developed countries to increase tion their rice harvest (应用) rice harvests being produced twice as large; 22% of people fed from just 7% Contribu of the farmland in China; the UN ridding the world of hunger -tion future
2021学年高中英语Unit2WorkingthelandSection4Writing课件新人教版
M 妙笔成篇
• Have you ever dreamt of tasting organic vegetables without chemical fertilizer every day？Please go to Green Leaf－an organic vegetable base.
• Located in the west of the city，it has expanded to a farm covering an area of more than 1， 000 mu in the past two decades.And it has been equipped with advanced facilities.What makes it different from others is that the vegetables here are grown without any chemical fertilizer.The rich soil makes these vegetables full of nutrition；as a result，they are exported to many countries in the world.
• (6)肥沃的土壤让这些蔬菜营养丰富。 • The rich soil m__a_k_es__th_e_se__v_eg_e_t_ab_l_e_s _fu_l_l _o_f _n_ut_r_it_io_n_____.
• 2．句式升级 • (7)用locate的过去分词短语作状语，连接(2)(3)句。 • Located in the west of the city，it has expanded to a
• It has expanded to a farm ___w_h_ic_h_c_o_v_e_rs__an__a_re_a_o_f_m_o_r_e_t_h_an__1_,0_0_0_m__u_____ in the past two decades.