选择知识点

Different weather makes people feel different.It influences health,intelligence and feelings.
In August,it is very hot and wet in the southern part of the United States.People there have heart trouble and other kinds of health problems during this month.In the Northeast and the Middle West,it is very hot at some times and very cold at other times.People in these states have more heart trouble after the weather changes in February or March.
The weather can also influence intelligence.For example,in a 1983 report by scientists,IQ of a group students were very high when a very strong wind came,but after the strong wind,their IQ was 10% below.The wind can help people have more intelligence.Very hot weather,on the other hand,can make it lower.Students in many schools of the United States often get worse on exams in the hot months of the year （July and August）.
Weather also has a strong influence on people's feelings.Winter may be a bad time for thin people.They usually feel cold during these months.They might feel unhappy during cold weather.But fat people may have a hard time in hot summer.At about 18 C，people become stronger.
Low air pressure may make people forgetful.People leave more bags on buses and in shops on low-pressure days.There is "good weather" for work and health.People feel best at a temperature of about 18 centigrade.
Are you feeling sad,tired,forgetful,or unhappy today？It may be the weather's problem.



People may have more intelligence when comes ______ .

A. a rain
B. very hot weather
C. a strong wind
D. low air pressure

How may low air pressure make people feel？ ______

A. Forgetful.
B. Sad.
C. Angry.
D. Tired.

In "good weather" of 18 centigrade, ______ .

A. people are very forgetful
B. people can't do their work well
C. thin people feel cold
D. people are in better health

The writer wants to tell us that ______ .

A. hot and cold weather influences all people in the same way
B. weather influences people's lives
C. IQ never changes during weather changes
D. there is a good kind of weather for people's work and health

Paper is an important part of modern life.People use it in school,at work,to make artwork and books,to wrap presents and much more.Trees are the most common material for paper these days.
So how do people make paper out of trees today？People first cut trees,load them onto trucks and bring them to a factory.Machines cut open the outer coverings of the trees,and cut the trees into pieces.Those pieces are boiled into a soup.After that,it is hit flat,dried and cut up into sheets of paper.
The entire process,from planting a small tree to buying your school notebook,takes a very long time.Just growing the trees takes 10 to 20 years.
Making tons of paper from trees can harm the planet.Humans cut down 80，000 to 160，000 trees around the world every day,and use many of them to make paper.Some of those trees come from tree farms.But people also cut down forests for paper,which means that animals and birds lose their homes.
Cutting forests down also contributes to climate change,and paper factories pollute the air.After you throw paper,it often takes the paper six to nine years to break down.That's why recycling is important.It saves a lot of trees,slows climate change and helps protect endangered animals,birds and all creatures that rely on forests for their homes and food.
So if paper isn't good for the environment,why don't people write on something else？The answer：They do.With computers,tablets and cellphones,people use much less paper than in the past.Maybe a day will come when we won't use paper at all—or will save it for very special books and artworks.



What can we know about making paper out of trees？ ______

A. It costs much money.
B. It takes a lot of time.
C. It is very easy and fast.
D. It is dangerous and difficult.

What is the impact of paper production？ ______

A. It promotes the recycling.
B. It does harm to the environment.
C. It slows down the climate change.
D. It protects the animals from losing homes.

How will we use paper someday in the future according to the text？ ______

A. Use it for artworks.
B. Use the recycled paper.
C. Treasure it occasionally.
D. Use it for books only.

What idea does the author want to express from the text？ ______

A. The good reasons for making paper.
B. The wonderful experience of making paper.
C. The necessary process of making paper.
D. The influence of making paper on environment.

In one of the world's most forbidding environments,Polar bears spend their summers roaming（漫步）the Arctic on large pieces of floating ice.They drift（漂移）for hundreds of miles,finding mates,hunting for seals,and fatting themselves up for the winter.Without the floating ice,the world's largest bears could not survive.Yet at this moment,the polar bears' Arctic habitat （栖息地） is melting away under it because of global warming.
Over the past three decades,more than a million square miles of floating ice has disappeared.Scientists predict that,if the current rate of global warming continues,most,if not all,of the bears' floating ice will be gone by 2100.As a result,the world's polar bears could face global dying out by the end of this century.
Already,the ice on the southern edge of the polar bears' habitat is melting about three weeks earlier than in the past.The loss of those key weeks leaves the bears less time to hunt,eat and store up fat.Once the ice melts, the bears must fast for up to eight months on land until the floating ice returns.As a result of early melting,there has been a 14 percent decline in the Hudson Bay polar bear population over the past ten years—a fall clearly caused by global warming.
Besides,a growing number of polar bears may be drowning（溺水）as they are forced to swim more often,and for longer distances,looking for ice sheets（冰原）.According to a report by the US Minerals Management Service,researchers observed four dead polar bears floating 60 miles off Alaska in September of 2006 and said it was likely that many other bears swimming far off shore also drowned.Scientists have concluded that the worldwide population of about 20，000 polar bears is likely to become smaller by more than 30 percent in the next 35 to 50 years alone.



What do polar bears usually do in summer？ ______

A. Look for relatives.
B. Hunt for food.
C. Store crops up.
D. Make friends with seals.

What disaster will happen to polar bears by the end of this century according to the text？ ______

A. Global drowning.
B. Global dying out.
C. Global hunger.
D. Global roaming.

What can be inferred from the underlined part in Paragraph 3？ ______

A. The bears will have to stay hungry longer.
B. The bears will have to roam faster.
C. The bears will have to stay quieter on land.
D. The bears will have to face a faster fall of its population.

Why do polar bears have to swim more often and farther？ ______

A. To search for food.
B. To build up bodies to survive.
C. To find places to land on.
D. To escape being hunted.

Coral reefs are some of the most diverse and valuable ecosystems on Earth.Coral reefs support more species per unit area than any other marine（海洋的） environment,including about 4，000 species of fish,800 species of hard corals and hundreds of other species.Scientists estimate that there may be millions of undiscovered species living in and around reefs.This biodiversity is considered the key to finding new medicines for the 21st century.Many drugs are now being developed from coral reef animals and plants as possible cures for cancer,viruses,and other diseases.
Healthy coral reefs support fisheries as well as jobs and businesses through tourism and recreation.About half of all managed fisheries depend on coral reefs and related habitats for a part of their life cycles.The National Marine Fisheries Service estimates the commercial value of U.S.fisheries from coral reefs is over ﹩100 million,Local economies receive billions of dollars from visitors to reefs through diving tours,recreational fishing trips,hotels,restaurants,and other businesses based near reef ecosystems.
Coral reef structures also buffer（缓冲）shorelines against 97 percent of the energy from waves,storms,and floods,helping to prevent loss of life,and property damage.When reefs are damaged or destroyed,the absence of this natural barrier can increase the damage to coastal communities from normal wave action and violent storms.Several million people live in U.S.coastal areas near coral reefs.Some coastal development is required to provide necessary infrastructure（基础设施）for coastal residents and the growing coastal tourism industry.
Despite their great economic and recreational value,coral reefs are severely threatened by pollution,disease,and habitat destruction.Once coral reefs are damaged,they are less able to support the many creatures that live on them and the communities near them.When a coral reef supports fewer fish,plants,and animals,it also loses value as a tourist destination.



Why is biodiversity important to medicines？ ______

A. It can reduce the prices of new medicines.
B. It can help make new medicines.
C. It can be used for medicines.
D. It can be used to cure diseases.

How do coral reefs protect shorelines？ ______

A. They protect people against sharks.
B. They completely avoid serious flooding.
C. They prevent people from being drowned.
D. They weaken most of the energy from waves.

What will happen if coral reefs are damaged？ ______

A. Most fish will die out.
B. Coastal cities will attract fewer tourists.
C. There will be no large fish.
D. The sea will be polluted.

What is the best title for the text？ ______

A. The Importance of Diverse Ecosystems
B. The Environments of Coral Reefs
C. The Importance of Coral Reefs
D. The Value of Biodiversity

More than a million tons a year of America's plastic rubbish are not ending up where they should.As many as 1，300 plastic grocery bags per person is landing in places such as oceans and roadways,according to a new study of U.S.
In 2016，the United States generated 46.3 million tons of plastic waste,by far the most in the world.Between 2.7% and 5.3% of that was mismanaged,according to a study in Friday's journal Science Advances. "If you took nearly 2.5 million tons of mismanaged plastic waste and dumped it on the White House lawn,it would pile as high as the Empire State Building," said Jenna Jambeck,an environmental engineering professor.
Previous studies hadn't put the United States among the 10 worst offending nations for plastic waste in oceans.That's because the U.S.Environmental Protection Agency only tracks what goes into official parts of the waste stream such as landfills （废物填埋场） and recycling centers.
"The new study provides a more realistic view of our mismanaged waste," said University of Toronto ecology professor Chelsea Rochman,who wasn't part of the study. "We consume a lot of plastic which then becomes plastic waste.We recycle very little of this material,which is a waste of resources."
"A large but hard to quantify part of the problem involves the 51% of U.S.plastic waste shipped abroad for recycling to countries that routinely mismanage waste," Law said.The situation has been converting since many countries have become more limiting about taking U.S.rubbish imports.American exports of plastic waste have declined dramatically since their peak in 2016.
The government is spending billions of dollars trying to fix the problem,with modernized recycling technology and new business models to reduce waste while urging compulsory recycled content standards for new products and packaging.
"The best thing you can do environmentally is to produce no waste at all," Jambeck said.



What can we know about the plastic waste in America？ ______

A. It is improperly dealt with.
B. It is increasing every year.
C. It is as high as a tall building.
D. It is finding its way into landfills.

What did former studies fail to focus on？ ______

A. How plastic waste is managed officially.
B. Why all plastic waste isn't recycled.
C. When plastic waste reaches its peak.
D. Where all plastic waste finally ends up.

Which of the following can replace the underlined word "converting" in paragraph 5？ ______

A. continuing
B. changing
C. existing
D. affecting

What problem might America face concerning plastic waste？ ______

A. The lack of capital for waste management.
B. The lack of modern technology.
C. The limit of waste exports.
D. The seriousness of waste.

Fibre is a key part of a healthy diet.Heath Canada recommends 25 grams of fibre per day for women and 38 for men.Although it's safe to say most people could include more fibre in their diet,a research review shows there's an ideal amount for gaining health benefits.
The World Health Organization（WHO）analyzed some research to help develop new dietary guidelines for fibre.The study,also looks at which types of foods prevent weight gain and protect against chronic （慢性病） diseases.The researchers looked at 185 studies and 58 clinical trials conducted over 40 years.They found 25 to 29 grams of fibre is ideal for health benefits.
The WHO research found that people eating the most fibre are 15 to 30 percent less likely to die earlier from any cause in comparison to those consuming less fibre.Similarly,people who eat fiber-rich foods are 16 to 24 percent less likely to suffer some diseases like coronary heart disease,stroke,type 2 diabetes,and colon cancer.
"So while you should probably be eating more fibre,the next challenge for the public is finding ways to do so," Dr.Okeke-Igokwe says.Not everyone is aware of the best options（选择）.Fibre functions differently.Some fibre in foods like nuts,seeds,beans,and some fruits and Vegetables help slow digestion.Other fire in foods such as wheat bran（麦麸），vegetables and whole grains helps food pass through your system more quickly.
The more processing a food has,the less fibre it typically has,according to the Academy of Nutrition and Dietetics.It's something to keep in mind to help reach your fibre goals.The Academy's other suggestions for hitting your daily fibre intake include changing over-processed grains for steel cut oats（燕麦）or replacing white rice with brown or whole grain options.You can also add to your diet as well as make substitutions.Luckily,you can find fibre in other various food combinations,too.



What is the WHO report mainly about？ ______

A. How people prevent diseases.
B. How much fibre you should eat daily.
C. The differences between men and women.
D. The significance of fibre in a healthy diet.

Where can you find the data that best supports "Fibre is necessary for health"？ ______

A. In Paragraph 1.
B. In Paragraph 2.
C. In Paragraph 3.
D. In Paragraph 4.

What is important in taking fibre according to Dr.Okeke-Igokwe？ ______

A. Eating more fibre.
B. Taking your time in eating.
C. Eating vegetables quickly.
D. Choosing proper foods.

Why does the author suggest changing over-processed grains？ ______

A. They contain less fibre.
B. They are less tasty.
C. They are easy to digest.
D. They have too much energy.

Did you know people who live in different parts of China have different habits and preferences？For example,people from southern China prefer to eat vegetables,while people from north China like to eat meat.According to a new study in a journal,gene variations（变异）might be responsible for these differences.Researchers from China's BGI collected genetic information from 141，431 Chinese women,who came from 31 provinces and consisted of 36 ethnic minority groups.
They found that natural selection has played an important role in the ways that people living in different regions of China have developed,affecting their food preferences,immunities（免疫力）to illness and physical features.
A variation of the gene FADS2 is more commonly found in northern people.It helps people metabolize（新陈代谢） fatty acids,which suggests a diet that is rich in flesh.This is due to climate differences.Northern China is at a higher latitude.This weather is difficult to grow vegetables in.Therefore,northerners tend to eat more meat.
The study also found differences in the immune systems of both groups.Most people in southern China carry the gene CR1，which protects against malaria.Malaria was once quite common in southern China.In order to survive,the genes of people in the south evolved to fight against this disease.However,people in the south are also more sensitive to certain illnesses,as they lack the genes to stop them.
Genes can also cause physical differences between northerners and southerners.Most northerners have the ABCC11 gene,which causes dry earwax,less body smell and fewer sweats.These physical differences are also more beneficial to living in cold environments.Southerners are less likely to have this gene,as it did not develop in their population.



What did the new study focus on？ ______

A. Regions.
B. Eating habits.
C. Gene variations.
D. Ethnic minority groups.

What is the main function of the gene FADS2？ ______

A. It helps store fat.
B. It helps digest meat.
C. It helps gain weight.
D. It helps treat an illness.

According to the study,most northerners ______ .

A. sweat less frequently
B. are immune to malaria
C. prefer vegetables to meat
D. are more sensitive to climates

How many differences did the study find related to genes？ ______

A. Two.
B. Three.
C. Four.
D. Five.

A Singaporean company will feed airport food waste to mealworms（黄粉虫）before turning them into fish feed（饲料），aiming to cut the country's use of imported feed and offer a continuous alternative.
Blue Aqua International will partner with Dnata,an air and travel services provider,to change organic waste at Singapore's Changi Airport into insect protein for aquacultural（水产养殖）use,according to a statement Tuesday.
The project looks to replace traditional fish and soybean meal as the main sources of protein for aquafeed.The insects will eat the food waste and change it into part of the body containing about 60 per cent protein.The dried baby worms will then be made into feed.
These mealworms can be a continuous solution to several problems.Using a small land and giving out less carbon,they turn food waste into feed and offer an alternative source of protein.Ynsect SAS，a small French business that keeps mealworms to feed fish and pets,attracted money from investors including Iron Man movie actor Robert Downey Jr.in a round of fund-raising last year.
The deal will give Singapore's farmers access to domestically produced animal feed,which is traditionally bought from abroad.The Southeast Asian nation imports more than 90 per cent of its food and has set a goal to produce a third of its food locally by 2030.It also aims to achieve a general recycling rate of 70 per cent by then.Presently,less than 20 per cent of Singapore's food waste is recycled.
As part of the partnership,Dubai-based Dnata will add Blue Aqua to its list of suppliers to buy locally farmed seafood for its catering service.



What is the function of mealworms？ ______

A. To cut the use of imported fish feed.
B. To eat food waste and make fish feed.
C. To domestically produce animal feed.
D. To replace traditional fish and soybean meal.

What does Paragraph 4 mainly talk about？ ______

A. The producers of the feed.
B. The purpose of the project.
C. The advantages of the project.
D. The composition of the feed.

What can we infer about Singapore from Paragraph 5？ ______

A. It is a rich country.
B. It is short of self-produced food.
C. Its recycling rate is very high now.
D. Its farmers don't support the deal.

What is the text mainly about？ ______

A. A new way to produce fish feed.
B. An introduction to a company.
C. A plan to reduce food waste.
D. A deal to protect farmers.

Based on a true story,the novel Safe ax Houses by Eric Walters is an amazing book.It is about a 13—year—old girl named Elizabeth Hardy who babysits the McBride children David and Suzie.One rainy,stormy evening they walk home from school.When they arrive home,water floods （淹没） the backyard,cuts the power and floods roads,which stops Mr.and Mrs.McBride from coming home.Soon the flooding begins to invade the McBrides' home and Elizabeth,David,Suzie and their dog Daisy try very hard to escape and survive the flood,
My favorite character is David because!find him very funny and brave,and although he can be stubborn and rude at times,he is still a nice and friendly person.As much as I want to be like David I could never be like him.At least,I don't think I could ever do something as brave as he docs.
I think Eric Walters does a great job in describing the characters and telling the story.I really feel like this all just happened in front of my eyes.Ever since I started reading Safe as Houses I never wanted to put the book down,and considering I was not a big fan of reading that did not happen very often.Safe as Houses changed my opinion in regard to reading and now I enjoy reading very much.
Eric Walters' writing career （生涯） all started in 1993 when Eric was teaching a grade 5 class.His students were not good readers and did not like reading,so Eric created a book called Stand Your Ground for his students and used some of the students' names to create the story.Ever since Eric published （出版） that book he has become a big time writer and has published many amazing different books like Camp X，Tiger Trap,Camp 30，We All Fall Down and Flyboy.



What happened on that particular evening？ ______

A. A 13—year—old girl got lost.
B. A terrible rainstorm broke out.
C. Three children were trapped on the way home.
D. The McBrides' home was completely destroyed by floods.

What does the author like about David？ ______

A. His creativity.
B. His great skill.
C. His personality.
D. His good behavior.

What can we infer about the author？ ______

A. He is a man full of courage.
B. He used to enjoy reading very much.
C. He is very like David in Safe as Houses.
D. He has been greatly affected by Safe ax Houses.

Why did Eric write Stand Your Ground？ ______

A. To record his students stories.
B. To encourage his students to read.
C. To state the importance of reading.
D. To teach his students they can be writers.

Chemicals are part of our daily life.All living and nonliving matter is made up of chemicals and virtually every man-made product includes the use of chemicals.Many chemicals can,when properly used,significantly contribute to the improvement of our quality of life,health and well-being.But other chemicals are highly hazardous and can negatively affect our health and environment when improperly managed.
Chemical safety is becoming an increasingly important topic around the world.I covers the handling and use of chemicals in a way that is safe for humans and the environment.It includes risk assessment and education in best and safe practices.It brings attention to potential danger and discusses safety in industrial,teaching and academic settings.
Chemical safety has many scientific and technical components.Among these are toxicology（毒物学），ecotoxicology and the process of chemical risk assessment which requires a detailed knowledge of exposure and of biological effects.
The International Programme on Chemical Safety（IPCS） works to set up the scientific basis for the sound management of chemicals,and to strengthen national abilities for chemical safety.
Chemical Safety is achieved by undertaking all activities related to chemicals.It covers all chemicals,and the full range of exposure situations from the natural presence of chemicals in the environment to their extraction （提炼），industrial production,transport,use and handling.
The Chemical Safety programme helps to address proper use,handling,and storage of these materials.These activities are extremely vital to a safe working environment.
The production and use of chemicals continue to grow worldwide,particularly in developing countries.This is likely to result in greater negative effects on health if sound chemicals management is not ensured.Multisectoral（多部门的） action is urgently needed to protect human health from the harmful effects of improperly managed chemicals.



What can best replace the underlined word"hazardous" in Paragraph 1？ ______

A. Important.
B. Harmless.
C. Dangerous.
D. Beneficial.

What is the target of the International Programme on Chemical Safety？ ______

A. Handling all kinds of chemicals.
B. Offering help for chemical safety.
C. Preventing chemicals from spreading.
D. Removing the harmful effects of chemicals.

According to the author,what should people do with chemicals？ ______

A. People should never use any chemicals.
B. People should manage chemicals properly.
C. People should stop using harmful chemicals.
D. People should produce as many chemicals as possible.

What is the passage mainly about？ ______

A. Chemical safety.
B. The importance of chemicals.
C. The production and use of chemicals.
D. The storage and transport of chemicals.