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How fit are your teeth？Are you lazy about brushing them？Never fear：An inventor is on the case.An electric toothbrush senses how long and how well you brush,and it lets you track your performance on your phone.
The Kolibree toothbrush was exhibited at the International Consumer Electronics Show in Las Vegas this week.It senses how it is moved and can send the information to an Android phone or iPhone via a Bluetooth wireless connection.
The toothbrush will be able to teach you to brush right（don't forget the insides of the teeth!）and make sure you're brushing long enough. "It's kind of like having a dentist（牙医）actually watch your brushing on a day-to-day basis," says Thomas Serval,the French inventor.
The toothbrush will also be able to talk to other applications on your phone,so developers could,for instance,create a game controlled by your toothbrush.You could score points for beating monsters among your teeth. "We try to make it smart but also fun." Several says.
Serval says he was inspired by his experience as a father.He would come home from work and ask his kids if they had brushed their teeth.They said "yes," but Serval would find their toothbrush heads dry.He decided he needed a brush that really told him how well his children brushed.
The company says the Kolibree will go on sale this summer,from ﹩99 to ﹩199，developing on features.The US is the first target market.
Serval says that one day,it'll be possible to replace the brush on the handle with a brushing unit that also has a camera.The camera can even examine holes in your teeth while you brush.



Which is one of the characteristic（特征）of the Kolibree toothbrush？ ______

A. It can sense how users brush their teeth.
B. It can track users' school performance.
C. It can detect users' fear of seeing a dentist.
D. It can help users find their phones.

What can we learn from Serval's words in Paragraph 3？ ______

A. You will find it enjoyable to see a dentist.
B. You should see your dentist on a day-to-day basis.
C. You can brush with the Kolibree as if guided by a dentist.
D. You'd like a dentist to watch you brush your teeth every day.

What is Paragraph 5 mainly about？ ______

A. How Serval found out his kids lied to him.
B. Why Serval thought brushing teeth was necessary.
C. How Serval taught his kids to brush their teeth.
D. What encouraged Serval to invent the toothbrush.

What can we infer about Serval's children？ ______

A. They were unwilling to brush their teeth.
B. They often failed to clean their toothbrushes.
C. They preferred to use a toothbrush with a dry head.
D. They liked brushing their teeth after Serval came home.

This activity will melt away the pounds,build your body and leave you on an emotional high.Yet the form of exercise,the fitness trend（趋势）of the year,does not require gym membership or a personal trainer.All you need to do is walk.
"Walking is a refreshing alternative to complicated aerobic（氧）routines and overpriced gym membership," says personal trainer Lucy Knight,author of a new book on the exercise. "It is free,enjoyable and already a part of everyday life.All you need to do is correct your technique,walk faster and for longer and you will lose weight？"
There is much evidence of the benefits of walking.Scientists at the University of Pittsburgh recently discovered that overweight people who walked briskly（快）for 30 to 60 minutes a day lost weight even if they didn't change any other lifestyle habits.Another American study found that people who walked for at least four hours a week gained less weight than couch potatoes as they got older.Researchers at the University of Massachusetts medical school found that people who walked every day had 25 percent fewer colds than those who sat a lot.Best of all,walking makes you feel good about yourself. "For people suffering from depression,walking three to four times a week for 30 minutes has been shown to lift their mood," says Knight.
But how to walk your way to weight loss and wellness？Health experts recommend that we should walk 10，000 steps a day to stay healthy.Actually,you would probably need to walk at least 16，000 steps a day to lose weight. "Your workout plans depend on your level of fitness.You should aim to progress by increasing your walking time by five minutes every two weeks,and walk a bit faster.In just three months,the results should speak for themselves," says Knight.



What is the latest fitness trend according to the passage？ ______

A. Brisk walking.
B. Losing weight.
C. Working out in a gym.
D. Exercising with a personal trainer.

The underlined word "overpriced" in paragraph 2 means ______ .

A. expensive
B. worthy
C. prepaid
D. discountable

Studies and researches are mentioned in the passage to show walking ______ .

A. is gaining increasing popularity
B. benefits people in different aspects
C. is an enjoyable way to lose weight
D. involves different groups of people

It can be learned from the last paragraph that ______ .

A. 1600 steps a day is needed for weight losses
B. the effect of walking is noticeable over time
C. your fitness level depends on your health experts
D. changing the walking time every day is necessary

Taking a picture of your tongue with a mobile phone could soon tell you how healthy you are.Researchers believe the images can reveal（揭示）important information about a patient's health and even give them early warning of serious illness.
A team at the University of Missouri is developing a system that can analyze（分析）pictures using a 5，000-year-old Chinese principle（原理），which is based on the flow and balance of positive and negative energies in the body,and uses the tongue as a key to learning about a person's physical health,or "zheng" according to Chinese medicine.
"Within a year,our goal is to create an application for smart phones that will allow anyone to take a photo of their tongue and learn the state of their zheng," said Dong Xu,chair of MU's Computer Science Department in the College of Engineering and the co-author of the latest study.
The software analyzes images based on the tongue's color and coating to distinguish between tongues showing signs of "hot" or "cold" zheng.Shades of red and yellow are connected with hot zheng,while a white coating on the tongue is a sign of cold zheng.
"Hot and cold zheng doesn't refer directly to body temperature," said Xu, "Rather,it refers to a series of symptoms（症状）connected with the state of the body as a whole."
For the study,263 gastritis（胃炎）patients and 48 healthy volunteers had their tongues analyzed.The gastritis patients were classified by whether they showed infection by a certain bacteria as well as the intensity（强度）of their gastritis symptoms.In addition,most of the gastritis patients had been previously classified with either hot or cold zheng.This allowed the researchers to test the accuracy of the software's analysis.
"Our software is able to classify people based on their zheng state.And as we continue to work on the software,we hope to improve its ability," said another co-author Ye Duan,"Eventually everyone will be able to use this tool at home using smart phone applications,which will allow them to monitor their zheng and get an early warning about possible ailments."



The software mentioned in the passage is based on ______ .

A. the latest development of smart phones
B. a traditional Chinese medical principle
C. the changes in one's flow and energy
D. symptoms connected with the state of the body

According to Chinese medicine,zheng refers to ______ .

A. one's body temperature
B. the physical health of a person
C. the possible disease of a person
D. the color and coating of one's tongue

The underlined word "ailments" can be replaced by ______ .

A. analysis
B. effects
C. illnesses
D. applications

It can be inferred from the passage that ______ .

A. the software still needs improvement
B. the subjects in the study are all gastritis
C. the software has been in market for a year
D. the subjects in the study are classified by age

Before the corona virus pandemic arrived in Italy,the big worry about tourism was overcrowding,as millions of tourists crowded the country's most popular spots like Florence,Rome and Venice.Then,with the pandemic,tourists disappeared.
According to most estimates,the tourism sector is not expected to recover to pre-pandemic levels until late 2023 or early 2024，but political leaders and many working in the sector are taking steps now to assure that,as the tourism strengthens,it avoids the former overcrowding problems in tourist centers.
"Italy should not emphasize the dependence on big tour buses that all pull into parking lots and overwhelm a small town for a few hours,but promote more high-quality tourism that shows visitors the country wonders beyond the few dozen places everyone knows about," Gianfranco Lorenzo,head of the research department for Florence's Center for Touristic Studies,says.There's no reason people should be lined up to see one famous site when there are many places that are just as important and just as impressive.
Those strategies are already in development.This summer many Italian cities are trying to focus the attention of visitors on outdoor attractions like sprawling gardens and architectural ruins,where visitors can remain spread out to keep corona-virus infection risks low.
Florence's Uffizi Galleries,one of the most visited museums in Italy,has launched the "Uffizi Diffusi" initiative which includes displaying some of its collections in museums in smaller towns to help draw tourists who might otherwise have spent their time in overcrowded Florence.
Lorenzo says reducing the impact of tourists does not mean the country will have to host fewer tourists in the future. "In a few years we could even have more tourists than we had before the pandemic," he says. "But for that to be sustainable,they just have to be spread out more evenly."



Why do the political leaders in Italy adopt certain strategies in the tourism sector？ ______

A. To protect visitors from corona-virus infection.
B. To settle the overcrowding problem in tourist centers.
C. To limit the number of tourists coming to Italy.
D. To host more foreign tourists in the near future.

The "Uffizi Diffusi" initiative has been launched to ______ .

A. draw more tourists
B. display great works
C. promote tourism industry
D. spread out visitors

What is Gianfranco Lorenzo's attitude towards the future of tourism in Italy？ ______

A. Optimistic.
B. Ambiguous.
C. Doubtful.
D. Concerned.

What can be a suitable title for the text？ ______

A. The Problem of Overcrowding in Italy.
B. The Future of the Tourism Industry in Italy.
C. The Reform of the Tourism Industry in Italy.
D. The Impact of Corona-virus Pandemic on Italy.

British sculptor Jason Taylor has made it his mission to use his talent to conserve our ecosystems by creating underwater museums.Over the years,the environmentalist has put over 850 massive artworks underwater worldwide.On February 1，2021，Taylor launched his latest work---The Underwater Museum of Cannes.
"The main goal was to bring attention to the fact that our oceans need our help," Taylor told Dezeen. "Ocean ecologies have been destroyed by human activity in the Mediterranean over the past few decades,and it is not obvious what is taking place when observing the sea from afar."
The Underwater Museum of Cannes contains 6 sculptures featuring local residents of various ages.They range from Maurice,an 80-year-old fisherman,to Anouk,a 9-year-old student.Towering over 6-feet-tall and weighing 10 tons,the faces are sectioned into two parts,with the outer part like a mask.The mask indicates that the world's oceans appear powerful and unbeatable from the surface but house an ecosystem that is extremely fragile to careless human activities.
Though the waters surrounding the sculptures now appear a pristine blue,the seabed was filled with old boat engines,pipes,and other human-made trash when the project began about four years ago.Besides removing the trash,Taylor also restored the area's seagrass.Just one square meter of the seagrass can generate up to 10 liters of oxygen daily.The seagrass also helps prevent coastal erosion and provides habitats for many ocean creatures.
"The idea of creating an underwater museum was to draw more people underwater and develop a sense of care and protection," Taylor told Dezeen. "If we threw unwanted waste near a forest,there would be a public outcry.But this is happening every day in our surrounding waters and it largely goes unnoticed."



What are the underwater museums intended to do？ ______

A. To make huge profits.
B. To raise awareness of protecting the ocean.
C. To show Jason Taylor's talent.
D. To draw attention to endangered sea animals.

Why does the outer part of the sculptures look like a mask？ ______

A. To popularize the features of the locals.
B. To remind people to protect themselves.
C. To reflect people's protection of the ocean.
D. To stress the sensitiveness of the ecosystem.

What's Paragraph 4 mainly about？ ______

A. How the project was started.
B. How the seagrass was restored.
C. What recovery effort the project made.
D. Why the surroundings were improved.

What can we infer from what Jason Taylor said in the last paragraph？ ______

A. The situation of the ocean is easily ignored.
B. The destruction caused to the ocean is noticeable.
C. Forests play a more important role in ecosystems.
D. People have zero tolerance to damage done to nature.

The starting point of herd immunity（群体免疫）for COVID-9 is still uncertain ，but many epidemiologists （流行病学家）believe it will be reached when between 60 percent and 80 percent of the population has been infected and develops resistance.A lower level of immunity in the population can slow the spread of a disease somewhat,but the herd immunity number represents the point where infections are generally less likely to turn into large outbreaks.
Studies that use the tests to examine only a small quantity of population,often called serology（血清学）surveys,are being undertaken around America and the world.The purpose of these new studies is to look for antibodies（抗体）in people's blood,proteins produced by the immune system that indicate a past infection.
An advantage of the tests is that they can pick out people who may have been infected and didn't know they were sick .A disadvantage is that the tests are sometimes wrong--and several studies,including a notable one in California,have been criticized for not taking the possibility of inaccurate results into consideration or for not representing the whole population.
While these studies are far from perfect,many countries,including parts of Sweden,are on track to achieve so-called herd immunity from the novel coronavirus-caused COVID-19 disease within weeks.In general,they give a better sense of how far the coronavirus has truly spread and its potential for spreading further.The starting point of herd immunity may differ from place to place,depending on factors like density and social interaction.



What do we know about herd immunity number from the text？ ______

A. The higher level of it,the better.
B. The lower level of it,the worse.
C. It is a point indicating a small number of infections.
D. It is a point indicating little chance of large outbreaks.

What kind of people can we get antibodies from？ ______

A. People who are sick.
B. People who are always healthy.
C. People who were once infected.
D. People who were killed by the disease.

What is the third paragraph mainly about？ ______

A. The contents of the studies.
B. Two sides of the studies.
C. The procedure of the studies.
D. The results of the studies.

Which of the following best describe the author's attitude towards the studies？ ______

A. He or she supports them.
B. He or she doubts their authority.
C. He or she thinks them perfect.
D. He or she partially believes in them.

Middle-aged spread cannot be blamed on a declining metabolism（新陈代谢），according to an analysis of the body's energy use.
The study,of 6，400 people,from eight days old up to age 95，in 29 countries,suggests the metabolism remains "rock solid" throughout mid-life.It peaks at the age of one,is stable from 20 to 60 and then unavoidable declines.The study,published in the journal Science,found four phases of metabolic life：First period,birth to age one,when the metabolism shifts from being the same as the mother's to a lifetime high 50% above that of adults.Second period,a gentle slowdown until the age of 20，with no sharp change during all the process of adolescence.Third period,no change at all between the ages of 20 and 60.Fourth period,a permanent decline,with yearly falls that,by 90，leave metabolism 26% lower than in mid-life.
Prof John Speakman,one of the researchers,from the University of Aberdeen,said,"The most surprising thing for me is that there is no change throughout adulthood-if you are experiencing mid-life spread you can no longer blame it on a declining metabolic rate."
People's metabolism was measured using doubly labelled water（双标水）.But doubly labelled water is incredibly expensive,so it took researchers working together across 29 countries to gather data on 6，400 people.
The researchers said fully understanding the changing metabolism could have a possible impact on medicine.Prof Herman Pontzer from Duke University said it could help reveal whether cancers spread differently as the metabolism changes and if drug doses could be adjusted during different phases.Prof Tom Sanders,from King's College London,said："Interestingly,they found very few differences in total energy use between early adult life and middle age-a time when most adults in developed countries put on weight".These findings would support the view that the obesity epidemic is fuelled by excess food energy intake and not a decline in energy use.



What do the researchers find about the metabolism？ ______

A. It gradually declines for adults.
B. The highest metabolic rate is at age 20.
C. It reaches the highest point in childhood.
D. Its decline has little to do with middle-aged spread.

In which section of a newspaper may this text appear？ ______

A. Science.
B. Business.
C. Entertainment.
D. Culture.

What's the difficult when conducting the study？ ______

A. The high cost.
B. The long research time.
C. Limited medical technology.
D. Selection of research objects.

It can be inferred from the last paragraph that ______ .

A. the changing metabolism could lead to cancers.
B. most adults gain weight because of taking in too much food.
C. energy use keeps the same from early adult life to middle age.
D. Sanders thought drug doses could be adjusted during different phases.

A trial project by the Montreal Children's Hospital suggested that the use of medical hypnosis（催眠）can reduce pain and anxiety in patients.The project also resulted in a reduction in the amount of medicines used to perform medical-imaging imaging（医学影像） procedures.
"During the examination children don't move.It works perfectly.It's amazing," said Johanne L'Ecuyer,a medical-imaging technologist at the hospital.
The project was inspired by a French team from Rouen University Hospital Centre where examinations are done under hypnosis instead of general anesthesia（麻醉）.
A French medical-imaging technologist-also a hypnotist — was invited to train a few members in the medical-imaging department of the children's hospital.In all,80 examinations were conducted for the project between January and September,2019，focusing on the imaging procedures that would cause anxiety.
Hypnosis is not a state of sleep：It is rather a modified（改变的）state of consciousness.The technologist will guide the patient to this modified state—an imaginary world that will disassociate itself more and more from the procedure that follows.
"The technologist must build up a story with the patient," Ms.L'Ecuyer said. "The patient is left with the power to choose what he wants to talk about.Do you play sports？Do you like going to the beach？We establish a subject that we will discuss throughout the procedure."
Everything that happens next during the procedure must be related to this story — an injection （注射）becomes the bite of an insect；the heat on the skin becomes the sensation of the sun and a machine that rings becomes a police car passing nearby.
"The important thing is that the technologist associates what is happening outside the patient's body with what the patient sees in his head," Ms.L'Ecuyer said. "It requires creativity on the part of the technologist,imagination,a lot of patience and kindness."
"The procedure appealed to the staff a lot when it was introduced in January.It spread like wildfire that someone from France was here to train the technologists," Ms.L'Ecuyer said.She added that she had a line of staff at her door wanting to take the training.



One of the results produced by the trial project is ______ .

A. a better understanding of children
B. less use of certain medicines
C. new medical-imaging technology
D. an improved reputation of the hospital

According to Paragraph 5，hypnosis works by ______ .

A. creating a perfect world for patients
B. forcing patients into a state of deep sleep
C. putting patients into an unconscious state
D. leading patients' consciousness away from reality

The procedure was received among the staff with ______ .

A. uncertainty
B. worry
C. enthusiasm
D. criticism

What is the passage mainly about？ ______

A. The use of hypnosis in medical-imaging procedures.
B. The standard method of conducting hypnosis.
C. An introduction of medical-imaging technology.
D. An easy way to communicate with patients.

What is soy（大豆）？And is soy bad for you？Nature is so amazing that everything is there.Soy is such a wonderful creation.The food is one of just a handful of complete vegetarian proteins.Soy products,for example,tofu,contain some important substances.Because your body is unable to products these important substances,they must come from food sources.
Regular intake of soy may help with reducing high blood pressure.In fact,a review study found that soy protein may significantly help your body work.Soy is also one of 13 foods that help to lower blood fat naturally.
The main function of soy is to benefit the heart.If you eat a number of heart-health-claim-approved protein foods,such as soy and nuts,you can get a drug-like cholesterol（胆固醇）reduction.So just because of the good effect,don't miss these foods.Add some of them to your diet.
"Soy foods have a lot of nutritional value that makes them especially appealing to folks interested in eating a heart-healthy diet," says Leman. "Whole soy foods have fiber and are low in fat.Soy foods can replace less heart- healthy choices,like red and processed meats."
In part,that's because healthy cholesterol levels benefit heart health.Many experts believe that soy is beneficial to the heart because analyses of the effect of soy have continuously shown that soy protein reduces cholesterol.
If you're wondering,"Is soy bad for you？" The answer could be "Yes"，if you're allergic（过敏的）to it,Soy is one of the top seven allergens in the United State-along with milk.eggs,tree nuts,fish,shellfish and wheat.An allergy to soy is common in children.See a doctor if you have any of the signs of allergy,and also learn the key facts about food allergies.



How does the author begin the text？ ______

A. By listing data.
B. By quoting poetry.
C. By asking questions.
D. By making comparisons.

What's the main advantage of soy？ ______

A. It is more delicious than meat.
B. It is convenient to cook.
C. It cures several diseases.
D. It is good for the heart.

What can be in inferred about soy from the last paragraph？ ______

A. It is harmful to some people.
B. It can't reduce cholesterol.
C. It contains as much protein as milk.
D. It won't cause allergic reactions.

What con be n suitable title for the text？ ______

A. Who Is Not Suitable to Eat Soy？
B. What Soy Really Does to Your Body？
C. What's the Best Way to Eat Soy Foods？
D. How Can You Avoid the Risk of Eating Soy？

Like you and your pet dog,plants are living things：they eat,drink,and grow.Unlike you and your dog,they can't run away,use fists or teeth,or hide under the covers when they're threatened.But they can fight back.
Why would a plant need to fight back？To avoid being eaten,of course!Plants have several ways of protecting themselves.A plant can grow in a hidden or hard-to-get-to place.Think of plants you've seen growing on steep,rocky cliff（悬崖）.Or,a plant could make only some parts of itself attractive to hungry insects and animals.For instance,if a plant produced really tasty leaves,herbivores（creatures that eat only plants）might eat the leaves instead of the seeds,which the plant needs for making more plants.Some plants have sharp or slippery（滑的）parts that discourage insects and other animals from getting too close,like the thorns（刺）on a rosebush.
But the most interesting way that plants fight back is by using chemicals.Plants take minerals from the soil and combine them into chemicals that do a lot of work.For example,plants produce chlorophyll（叶绿素），which helps convert sunshine and water into the sugars that plants eat.
They also produce chemicals to help protect themselves.One kind of tobacco plant releases a chemical into the air whenever small bugs begin to eat it.The chemical signals large bugs,saying "Dinner's ready!" The big bugs come to eat the little ones and save the plant.
Most plants use chemicals in a more direct way against their enemies.In other words,plants make poison.



What does the underlined word "convert" mean？ ______

A. Change.
B. Separate.
C. Form.
D. Produce.

What do we know from the passage？ ______

A. Some plants hide under the covers when faced with threat.
B. A plant grows in a hard-to-get-to place to draw people's attention.
C. Some plants produce tasty leaves to protect their seeds.
D. Plants produce chemicals to meet the needs of big bugs.

What may be talked about following the last paragraph？ ______

A. Different effects that different plant poisons cause on plant eaters.
B. Different kinds of plants in the world.
C. Why plants make poison？
D. How to protect plants？

What would be the best title for the passage？ ______

A. Plant information
B. Plant enemies
C. Plant poisons
D. Plant protection