I think there are several reasons that suggest developing robots is a waste of money．
In San Diego recently ＄ 325，000 was spent on inventing a robotic squirrel to do some scientific experiments． The research proved that squirrels are able to scare away snakes by wagging （摇动） their tails． Do you need a robotic squirrel to work this out？
What about AIBO，a robotic pet，developed in Japan？ In Japanese aibou means "buddy"． These pets have been developed at huge cost mainly to provide entertainment．They've been used in movies and music videos． Universities have used them for educational purposes．However， in 2006 the company stopped producing these robotic pets in order to save money． Was it worth a lot of money？
Then there's NAO， a robot which has been developed by a French company．Its main purpose is to make life easier for humans． It speaks 19 languages and has its own personality．It can tell children a story， help in the classroom or the home， or act as a companion to those people who need someone to be with．A fully developed one costs ﹩16，000． Is that value for money？ Who can afford it anyway？
There may be good reasons why it is worth developing robots， but so far I haven't thought of any．
（1）What does the underlined word "companion" in Paragraph 4 mean in Chinese？
A．公司
B．机构
C．对手
D．伙伴
（2）What is the true fact about the robots mentioned？
A． The robotic squirrel is needed by every scientist to do some research．
B． AIBO wasn't made any more because it only provided entertainment．
C． A fully developed NAO may tell kids stories in different languages．
D． All the three types of robots used to be produced at a very low cost．
（3）What does the writer think of developing robots？
A． It can help bring people a lot of fun．
B． It has advantages in many ways．
C． It may be useful but costs too much．
D．It is worth a great deal of money．
Weekly Round﹣up
①The number of Chinese studying abroad grew at a slower rate（比率）in 2018， as more students have come to realize that studying abroad does not guarantee（保证） a well﹣paid job in foreign countries． About 78 percent of Chinese students abroad plan to work in China either right after graduation or after working abroad for a while． |
②Tours that provide a windows on wildlife without harming the animals are a welcome development for Chinese animal﹣lovers， a recent survey found．About 60 percent of interviewees said that they would refuse to take part in tours that might badly influence the normal life of animals in the wild or be harmful to wildlife． |
③A survey by American Councils for International Education，showed that there were 227， 086 Chinese learners across the formal US education system， making Chinese the third most popular language being studied． |
④Passengers found eating or drinking on the Beijing subway who do not stop when they are asked will face having their actions noted on their social credit（信用） score according to Beijing Municipal Commission of Transport． |
（1）Which of the following is true according to News 1？
A． Most Chinese students studying abroad plan to work in China．
B． Most Chinese students will no longer go abroad for education．
C． Chinese students studying abroad can find jobs easily in China．
D． Chinese students studying abroad can get well﹣paid jobs in China．
（2）What's the main idea of News 2？
A． Chinese tourists will not do any harm to wildlife from now on．
B． The tours are specially designed for Chinese to protect wildlife．
C． Many tourists in China have a strong sense of animal protection．
D． The tours make more tourists become interested in wild animals
（3）According to the news above， we know that ．
A． 227，086 Chinese learners have been to America to study languages．
B． Chinese has become the most popular language in the United States．
C． passengers are not allowed to drink or eat on the Beijing subway．
D． passengers will be punished and fined if they eat or drink on the subway．
Influenza， or flu（流感）， is a type of virus． It spreads from one person to another quickly． When someone who has the flu coughs or sneezes， little droplets from their lungs （肺） spread out into the air．Anyone nearby can get sick． Even a person who touches something with the virus and then touches his or her mouth， eyes， or nose， can become infected（感染）．
The outbreak of the 1918 influenza infected about 500 million people worldwide． It killed from 20 million to 50 million people． It was first seen in Europe， the United States， and parts of Asia．It then spread quickly around the world． Many people who became sick were young， healthy adults．At the time， no treatments worked in the prevention of the spread of the killer flu． People were ordered to wear masks． Schools， theaters and other public places were closed．
When the first wave（波＞in the spring of 1918 hit， it didn't seem serious． People who were infected felt the usual flu symptoms（症状）， which are chills， fevers， and feeling tired． Those who got sick generally got better after several days． Not many died． However， a second， highly contagious（传染的）wave of influenza appeared in the fall of that same year． Victims died shortly after they were infected ﹣ within hours or days． Their skin turned blue and their lungs were filled with liquid（液体），making it very difficult to breathe．
By the summer of 1919， the flu pandemic（大流行病） came to an end． Sick people had either got well or died． Almost 90 years later， in 2008， researchers announced they'd discovered why the 1918 flu was so deadly． The flu virus inflamed （使…恶化）the lungs， causing them to fill with liquid．
Since 1918， there have been several other influenza pandemics， although none has been quite as deadly．
（1）What information about the 1918 flu is mentioned in the passage？
A． The reason why it was so deadly．
B． The reason why it ended．
C． The change it caused to medical research．
D． The place in which it was last seen．
（2）All the people that were infected with the 1918 flu ．
A． had blue skin that led to their death
B． had touched someone with the virus
C． died as their lungs were filled with liquid
D． had the virus in their bodies that made them sick
（3）Which of the following statements about the 1918 flu is TRUE according to the passage？
A． Wearing a mask was the best way to treat it．
B． A younger person had a lower risk of being infected with it．
C． People expected the coming of its second wave， but couldn't stop it．
D． It was deadlier than any other influenza pandemic in modern history．
A Pioneer for all People
Though he was one of China's most famous scientists，Yuan Longping considered himself a farmer，because he worked the land to do his research.
Known as "Father of Hybrid Rice （杂交水稻）"，Dr Yuan graduated from Southwest Agricultural （农业的） College in 1953.From then on，finding ways to grow more rice was his life goal.As a young man，he saw the great need for increasing the rice production.At that time，hunger was a serious problem in many parts of the countryside.Dr Yuan searched for a way to get more rice with the same size of the fields.In 1974，he became an agricultural pioneer in the world to grow rice that has high production and that is called super hybrid rice.In the 1980s，he went around the world and gave advice about growing rice to farmers in other countries.In 2004，he won the World Food Prize for his work.
Dr Yuan was quite satisfied with his life.He would much rather keep time for his hobbies.He enjoyed playing the violin，swimming and reading.Spending money on himself meant very little to him，so he gave millions of yuan to help some researchers with their research in farming.
Long ago Dr Yuan had a dream about rice plants as tall as sorghum （高粱） .With his hard work，he grew the rice that could feed more people.President Xi Jinping praised him for his great contributions （贡献） to China's food safety and world corn development.
Answer the questions according to the passage. （必须使用完整语句作答）
（1）Why did Dr Yuan consider himself a farmer？
（2）What is Dr Yuan known as？
（3）When did Dr Yuan win the World Food Prize？
（4）How did Dr Yuan help other researchers？
（5）What did Dr Yuan make contributions to according to President Xi Jinping？
Earlier this year， China achieved a new milestone （里程碑） in space research． On January 3， 2019， Chang'e﹣4 became the first lunar probe （月球探测器） in history to successfully land on the far side of the moon．
The Earth's gravity （重力） slows the moon's rotation （自转）， matching it to the speed of its orbit （公转）． Therefore， the far side of the moon is almost "dark" and has never been seen． It's this sense of the unknown that makes the far side of the moon such an interesting place for scientific and space research． Being blown by solar （太阳的） winds， the far side may have the special minerals （矿物质 ）． For this reason， Chang'e﹣4 will study the effect of solar winds on the lunar surface and any mineral found by the spacecraft． Chang'e﹣4 is also carrying flower seeds， potatoes and silkworm eggs to see whether life is possible on the moon． If it is， then the moon will become a possible choice for space travel in the future．
However， research of the "dark" side isn't easy． As the far side is blocked（阻断） off from us， radio noise coming off Earth is also blocked． This is why China's relay satellite （中继卫星） Queqiao was sent up in May， 2018． Thanks to Queqiao， the communication problem between Earth and Chang'e﹣4 has been well solved．
Power supply （电源供应） is also a challenge to the task． Chang'e﹣4 gets energy from the sun through its solar panels． As we know， a lunar day has the length （长度） of 28 Earth days． After Chang'e﹣4 was sent up on December 8， 2018， it took the probe over 20 days to orbit the moon to be in a position to be able to land in moon daylight and use its solar panels．
Luckily， everything goes well， Chang'e﹣4 has worked on the "dark" side for over 5 months． It has sent back many photos of the far side of the moon and has been used to carry out some scientific experiments．
The New York Times used the word " groundbreaking" to praise the task and wrote that "it will offer help to the history and development of the moon"．
（1）When was Chang'e﹣4 sent up？
A． In May， 2018．
B． On December 8， 2018．
C． On January 3， 2019．
D． The passage doesn't tell us．
（2）The main tasks of Chang'e﹣4 don't include ．
A． studying if life is possible on the moon
B． studying the effect of solar winds on the lunar surface
C． solving the communication problem between Earth and other probes
D． researching any mineral found by the spacecraft
（3）The meaning of the underlined word "groundbreaking" in the last paragraph is the closest to " "．
A． harmful
B． unpredictable
C． risky
D． pioneering
（4）According to the passage， which of the following statements is NOT true？
A． Chang'e﹣4 has sent back many photos of the far side of the moon．
B． A lunar day has the length of 28 Earth days．
C． China's relay satellite Queqiao was sent up in order to offer power supply to probes．
D． Chang'e﹣4 is the first lunar probe in history that has successfully landed on the "dark" side of the moon．
Mike Isaac and I are reporters of Student Daily． For the topics of our newspaper next month we visited Sunshine Elementary School on May 10． We interviewed some students and here is what they said．
（1）What did Mike Isaac and the writer visit Sunshine Elementary School for？
A．For environment protection．
B．For wildlife protection．
C．For good manners in school．
D．For topics of the newspaper．
（2）What may cause people to be mad at one another in Andrew Vargas's opinion？
A．Losing more oxygen．
B．Speaking in a loud voice．
C．Cutting down more trees．
D．Hunting tigers for medicine．
（3）Who talked about health？
A．Joslyn Frace．
B．Jayden Mitchell．
C．Andrew Vargas．
D．Joseph Truong．
The population of the world continues to increase， but in some areas the population is falling．This is true in Europe and especially in Eastern Europe． In Russia， the population is going down by about 100 people EVERY HOUR! Russia's population could fall by ONE THIRD by the year 2050! And in Poland （波兰）the population is also going down because people are leaving to work in other countries．
One of the main reasons is a change of lifestyle． All over Europe people， especially educated women， have a different attitude （态度）to children than their parents．"I have one child and she is enough for me， "said Galina Tereschkova， a doctor from Moscow． "My husband and I both work full﹣time． We can't imagine having more than one child． "Many women decide to have children later in life or not to have children at all． "I don't want to have any children until I have worked for at least 10 years， "said 19﹣year﹣old student Hana Markova from Prague． Her opinion is typical of 18﹣24 year old women everywhere in Europe．
In Poland， the population is going down for a different reason． A lot of people，usually aged between 20 and 30， are leaving the country to work abroad． Poland joined the European Union in 2005 and since then more than half a million people have moved to Britain， Germany， Spain and Italy． Even so， the population of those four countries and many other countries in West Europe is also going down．
Many governments are now encouraging people to have larger families． In France，women now receive nearly 1，000 a month for a year if they have a third child．Austrian women receive 700 a month for three years when they have their first child．
（1）Where in the world is the population getting smaller？
（2）How many children does Galina Tereschkova want to have？
（3）What does Hana Markova want to do before she has children？
（4）Why is the population in Poland going down？
（5）How does the French government encourage people to have larger families now？
Most viruses can be found and killed by our immune system as soon as they enter our bodies.However，some viruses，for example，the coronavirus，are sneaky.They are difficult to recognize and find.These viruses can cause deadly diseases，like COVID﹣19.Human﹣to﹣human transmission can easily occur，and pandemic will therefore break out.Vaccination is by now a simple，safe and effective way to protect us from the diseases.
▲Vaccines are something that "looks" exactly the same as the viruses，mainly made from the viruses that are weakened or killed.They will not make us really ill.They only stimulate and activate our immune system to work，telling it something harmful is coming in.The immune system will know what the "viruses" look like，and send B cells（lymphocytes）or antibodies to find and kill them.Meanwhile，B cells will remember them for the next kill.A vaccine may also give us passive immunity by providing B cells taken from an animal or a human to play the same role.
Scientists have developed more than 180 vaccines to fight against COVID49.The technical approaches of these vaccines can be a little different，but their aims are the same.
Take the inactivated vaccine as an example.In an inactivated vaccine，the coronaviruses are already killed or made into the ones unable to produce more new viruses.When the immune system "sees" them，it will try to kill them.The question is：without enough these viruses• how can B cells remember them？That's why we need to take the vaccine more than one time.Though this vaccine is safe，it might not be as effective as it is expected to be.
The live﹣attenuated vaccine is different.In this vaccine，the viruses are weakened，but they are alive.They can produce enough new viruses to train the immune system to kill and remember them，so people only need to take the vaccine once.The live﹣attenuated vaccine is considered the most effective，but there is a worry：what might happen once these viruses wake up？
Therefore，although vaccination is by now one of the best ways to protect us from COVID﹣19，it can be better.
（1）The coronavirus can .
| A． |
not be killed |
| B． |
not be found |
| C． |
cause deaths |
| D． |
stop pandemic |
（2）Which of the following can be the best topic sentence of Paragraph 2？
| A． |
Vaccination can provide us with B cells. |
| B． |
Vaccines are made from different viruses. |
| C． |
Vaccination can prepare us against viruses. |
| D． |
Vaccines won't make us ill as the viruses do. |
（3）Compared to the inactivated vaccine，the live﹣attenuated vaccine .
| A． |
needs taking more than once |
| B． |
is equally safe |
| C． |
contains viruses that are killed |
| D． |
is more effective |
（4）What can we learn from the passage？
| A． |
Vaccination is good enough to treat COVID﹣19. |
| B． |
The immune system can be more effective with vaccines. |
| C． |
The viruses in inactivated vaccines can make new viruses. |
| D． |
180 vaccines have been developed to fight against diseases. |
If you wear glasses， there's good news for you．（1） A new study has found that needing to wear glasses is connected with higher levels of intelligence．
In the study， researchers from the University of Edinburgh studied data（数据）on brainpower and genes． Genes， made up of DNA， are information in the cells of our body． They determine how we look and how our bodies work． （2） They found a connection between brainpower and physical characteristics including eyesight and health． People who were more intelligent were more likely to have genes that might show they need to wear glasses． The researchers also found that being smarter has some advantages． They found ways in which smarter people have fewer health problems．
（3） They are not proved（证实的）causes． It is easy to prove that two things are connected． It is harder to prove that one thing， like intelligence， causes the other， like needing glasses．
Forget genes though． Wearing glasses makes people think you are more intelligent， even if you don't need them． A number of studies have found that people who wear glasses are usually seen as smarter， more hard﹣working and honest． （4） They get the people they work for on trial（审 判）to wear glasses． Glasses are also used to show someone is intelligent in movies and on TV．
（5） People who do not need glasses sometimes wear them． They wear them just to look smart or cool． Glasses are not only for needs． Wearing glasses can also be cool． Many movie stars are fans of fashion glasses．
A．Many lawyers use this to help them． B．We must try our best to protect our eyes． C．However，these are all simply connections． D．You might be smarter than those who don't． E．Ideas about wearing glasses have begun to change． F．Wearing glasses sometimes makes people look silly． G．The researchers studied the genes of over 300，000 people． |
China has named the nation's first Mars rover（火星车）Zhu Rong.For all of us，Zhu Rong is a well﹣suited name.
In an ancient Chinese story，Zhu Rong had the face of a man and the body of an animal.He rode on two dragons.When he had a big fight with Gong Gong，the god of water，Zhu Rong won.But after the fight，the human world came into complete darkness.Then he brought fire from heaven（天国）to the world.
"Zhu Rong is regarded as the earliest god of fire in traditional Chinese culture，" a space official said. "The first Mars rover was named Zhu Rong.The name symbolizes（象征）light and hope for space exploration（探索）in our country，and means to guide humans to continue exploration."
After leaving the earth last summer，Zhu Rong circled Mars for several months and landed on it in May.In recent years，our country has sent up the world's first quantum satellite（量子卫星），and Chang'e﹣4 has made a soft landing on the moon.We have made great progress in space technology and will soon start building our own space station.
（1）What Zhu Rong brought from heaven to the world was .
| A． |
fire |
| B． |
wars |
| C． |
water |
| D． |
animals |
（2）For China's space exploration，the name Zhu Rong symbolizes .
| A． |
a big fight |
| B． |
complete darkness |
| C． |
light and hope |
| D． |
Chinese culture |
（3）The underlined word "it" in the last paragraph refers to" "
| A． |
the earth |
| B． |
Mars |
| C． |
the moon |
| D． |
the sun |
（4）According to the passage，we can infer that .
| A． |
Zhu Rong is a bad person in an ancient Chinese story |
| B． |
China has made great progress in space technology |
| C． |
the writer is proud of China's space technology |
| D． |
the official doesn't like the name Zhu Rong |
Delivering a better life
By YANG FEIYUE |China Daily |Updated， 2019﹣03﹣30 10：42
A father who was disabled at work and abandoned （抛弃） by his wife brings his daughter on his takeout routes．
The 39﹣year﹣old man from Yunnan Province lost his mother when he was a teenager， He experienced a serious accident in 2012． And his wife abandoned him and their daughter three years ago．
But Li Bangyong didn' t give up．
He has managed to support himself and his girl by delivering takeout over the past two years．
Li moved to Jiaxing， Zhejiang Province to find a job but lost it after a machine crushed（压碎） his right hand．
He started delivering food with his baby last year． He put a safety chair on his e﹣bike． His girl wears a special coat to protect against sunlight and a quilt to keep warm．He works this way from 7：30 a．m． to 7 ：30 p．m． with only a 10﹣minute lunch break． He feeds his girl bread when she cries and slows down when she falls asleep． Li always carries her when he takes the food to customer' s doors， although he often has to climb many stairs．
He faces hardship but finds comfort in his work．
And many people have offered support to Li after reading his story．
（1）Who reported the news？
A． Yang Feiyue．
B．Li Bangyong．
C．Wang Zhenyu．
（2）How long does Li Bangyong usually work every day？
A．About 8 hours．
B． About 10 hours．
C． About 12 hours．
（3）Why does Li's girl walk around during a break？
A． To deliver takeout．
B． To relax her legs．
C． To protect against sunlight．
（4）Where does this passage probably come from？
A．A guide book．
B．A TV program．
C．A website
Recently， a designer in Hong Kong has invented a special book that can transform （变形） into a piece of furniture． The special book is called Bookniture． It can be unfolded to become a chair or a small table． People can either carry it around for a portable （轻便的） chair or can store it in their homes to use as extra furniture．
The book was designed by Mike Mak． He came up with the idea after never having enough seats for his friends in his home in Hong Kong．
"I love having friends at my place， but I have never had enough seats for everyone﹣we would always end up with just sitting on the floor． 1really want a seat that doesn't take up any floor space when I don't need it． One day， the empty space on my bookcase drew my attention． Then came the new idea﹣Bookniture， furniture hidden in a book，" said the 30﹣year﹣old designer．
Made from fully﹣recyclable kraft paper （牛皮纸） ， the book measures 33 cm by 18 cm． It expands （扩大） to 14 times bigger once it's opened， and can support up1，000 kg of weight． It comes in two colors， brown and black， and can be bought for between ￡55 and ￡57．
（1）The book is special because ．
A． it can be used as a bag to carry things
B． it is made from recyclable plastic
C． it can transform into a chair or a table
（2）Paragraph 3 is about ．
A． how Mike came up with the idea
B． who designed Bookniture
C． what Bookniture looks like
（3）What information can we learn about Bookinirure from the last paragraph？
①size
②color
③weight
④price
⑤material
A． ①②③④
B． ①②④⑤
C． ②③④⑤
（4）What can be the best title for this passage？
A． Bookniture．
B． Furniture．
C． Mike Mak．
A photo of a boy who arrived at school with a head full of icicles（冰柱） has drawn widespread attention to children from poor rural families．
Wearing only a thin jacket， Wang Fuman， 10， had braved ﹣9℃ weather to travel over an hour from his village home to reach Zhuanshanbao Primary School in Zhaotong， Yunnan province． "After walking more than 4 kilometers through the freezing snow， he arrived with his hair and eyebrows completely frozen， causing laughter among his 16 classmates， "said Fu Heng， the school's principal， who uploaded（上传） Wang's photos on Monday morning． Fu added that his classrooms do not have heating because of a lack of money．
After hearing Wang's story， the Yunnan China Youth Development Foundation offered a public donation（捐赠） for children from poor families on Tuesday． It has promised to give each needy child 500 yuan（＄75）to help them stay warm in winter． By 1： 00 p．m． on Wednesday， the provincial foundation had collected over 300，000 yuan in public donations according to their websites．
Wang， who has been nicknamed" Snowflake Boy"（冰花男孩） by netizens（网友）， became well﹣known online． By Wednesday morning， his picture had been "liked" more than 260，000 times on Sina Weibo． "Many children in cities don't have the strong willpower of this boy． I hope all his efforts will be rewarded（回报）． " a netizen wrote on Sina Weibo．
The name Fuman translates as "full of happiness"， but Wang does not come from a rich family．He lives in a mud hut（土坯房）with his grandmother and elder sister， and seldom sees his parents because they are migrant workers in other cities．
"I love school． We can have bread and milk for lunch， and we lean lots of things in class．" Wang said． His village now has electricity and tap water， "and my family is getting help to build a new house close to the school"， he said． "I think our life will get better．"
（1）Why did Wang's classmates laugh when he came in？
A． Because they thought Wang was poor．
B． Because they wanted to laugh at him．
C． Because he appeared with a head full of icicles．
D． Because Wang was late for class again．
（2）What did the netizens do according to the passage？
A． They took photos of Wang Fuman and uploaded them in time．
B． They expressed their support and admiration．
C． They promised to give each needy child 500 yuan．
D． They helped Wang return to school．
（3）The underlined phrase "a lack of money" can be replaced by" "．
A． being short of money
B． losing money
C． plenty of money
D． saving money
（4）What can we know from the passage？
A． The Yunnan China Youth Development Foundation offered a public donation for Wang Fuman on Tuesday．
B． Wang's village doesn't have electricity and tap water now．
C． Wang loves school just because he can have bread and milk for lunch．
D． The children got help quickly because of social love and convenient Internet．
Some people seem to have unusual memories． Zheng Aiqiang， a "memory athlete" on TV show Super Brain， can remember 2， 660 numbers in just one hour!
You would think people like him must have special brains． But according to a recent study by researchers from America and Holland， the brain structure （结构） of ordinary people and 23 of the world's lending memory athletes shows no difference．
Good memories can be trained． New research in the magazine Neuron suggests that a person will get a super memory with just six weeks of hard training．
Researchers found that a technique （技巧） called loci， invented by the ancient Greeks， can greatly help improve memory．
By using loci， you are using your imagination to improve the brain's memory networks． You can link （关联） something you need to remember with a place that you know very well． For example， to remember a list of numbers， imagine yourself walking through your house． Each thing is linked to a number． For example， zero could be the handle on the door and five could be the painting on the wall．
In one study， some ordinary people were given 20 minutes to remember 72 nouns． At the beginning， they could only remember 26 words， but when they were taught loci， they could remember 62 words．
"Not everyone can become a memory winner． But everyone using the technique can improve his memory greatly，" said Boris Konrad， one of the researchers in the study．
（1）From the recent study， we know that ordinary people and memory athletes have similar ．
（2）To memorize a list of numbers by using loci means you are using your to link it with a you know well according to the passage．
◆（3）请根据短文内容回答问题
What does the new research in the magazine Neuron suggest？
◆（4）请用一句话概括段落大意．
Paragraph 6 tells us that
◆（5）请将文中划线句子译成汉语．
Rice is one of the most commonly eaten basic foods around the world.Buying it and cooking it is a daily matter.Yet for many，its presence has been a matter of life and death.It is a main food because it is easy to grow，besides low cost and convenience.A poor community in the developing world may find it difficult to bring in foreign fruits or raise cattle for meat，but it can almost certainly use the land it has in order to grow plenty of rice.
This was the great achievement of Yuan Longping，who passed away on May 22 this year.A great Chinese scientist，Yuan successfully developed what is known as "hybrid rice" which can produce up a 30% higher output.Yuan Longping was born in the year 1930，a time when China was very different.It was a nation，without modern industry，depending on the rice which they grew.The first few decades （十年） of his life were met with major social events，and a rapidly growing population that made food supply not last all the time.This experience left its mark on Yuan Longping，which made him focus on （关注） farming science and work on his research of hybrid rice.
His achievement would see the rice supply in China increasing from 56.9 million tons in 1950 to 194.7 million tons by 2017.By 1991，20% of the world's rice output came from hybrid rice，even if only being planted in 10% of fields.
Always remember，human development begins first with the most basic and sample things，such as developing rice.We should be thankful for scientific thinkers like Yuan.
（1）Why is rice a main food around the world？
（2）What did Yuan develop successfully？
（3）When was Yuan Longping born？
（4）What made Yuan focus on farming science？
（5）How many tons was the rice supply in China by 2017？
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