It happens every spring. Flowers suddenly burst out everywhere on the same day as if they were in tune with one another. But how exactly do plants “know” when to flower?
It is a question that has puzzled biologists for years. But according to Science Daily, a US research group may have finally answered it-the secret lies in the protein called FKF1. This allows plants to sense the differences in day lengths so that they can tell the seasons are changing.
Researchers spotted the FKF1 protein when they were studying a plant called Arabidopsis. We found that the FKF1 protein is a photoreceptor（感光器）. This means it is sensitive to, and can be activated by sunlight.
Plants produce the protein every day in the late afternoon throughout the year. If there is no light at this time, for example, in winter, when the sun goes down early, the protein won’t be activated. But when spring comes and the days get longer, the FKF1 protein can be activated by daylight as the plants “know” it is time to flower. “The presence of light in the late afternoon is the signal for plants that the days are getting longer and that it is the best time for flowering.” explained Pakato Imaizumi assistant professor at the University of Washington and leader of the study.
The daylight-sensing system also keeps plants from flowering when conditions are poor for growing, such as during autumn or winter. When the weather is cold and days are short.
Although researchers have only studied how the FKF1 protein works in the Arabidopsis, they believe that the process is similar in many other more complex（复杂的）plants, including crops like rice and wheat. This could be useful to the agricultural industry.
“If we can control the timing of flowering, we might be able to increase crop yield by quickening or delaying this.” Imaizumi said “Also, if we could control the timing of flowering in horticultural plants, they may be worth more commercially（商业上）.”
New technology based on this research might also lead to higher use of biofuel（生物燃料）plants. This would be helpful for providing energy.
1. How do plants know when to flower?| A．They are naturally timed to flower. |
| B．They receive messages from other plants. |
| C．A certain protein tells them the time to flower. |
| D．Sunlight produces a certain protein to help them flower. |
| A．Flowers cannot tell the seasons are changing. |
| B．Plants are sensitive to cold weather and shorter days. |
| C．We are getting closer to controlling plant flowering times. |
| D．Researchers have studied how the FKF1 protein works in rice and wheat. |
| A．How seasons are changing |
| B．How plants know when to flower |
| C．What people can do with plants |
| D．What kind of plant Arabidopsis is |
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The honey guide does not actually like honey, but it does like the wax(蜡) in the beehives (蜂房). The little bird cannot reach this wax, which is deep inside the bees' nest. So, when it finds a suitable nest, it looks for someone to help it. The honey guide gives a loud cry that attracts the attention of both passing animals and people. Once it has their attention, it flies through the forest, waiting from time to time for the curious animal or person as it leads them tot he nest. When they finally arrive at the nest,
Scientists do not know why the honey guide likes eating the wax, but it is very determined (下决心) in its efforts to get it. The birds seem to be able to smell wax from a long distance away. They will quickly arrive whenever a beekeeper(养蜂者) is taking honey from his beehives, and will even enter churches when beeswax candles are being lit.
1. Why is it difficult to find a wild bees' nest?
| A．It'ssmallinsize. | B．It'shiddenintrees. |
| C．It'scoveredwithwax. | D．It'shardtorecognize. |
| A．Abee. | B．Abird | C．Ahoneyseeker. | D．Abeekeeper. |
| A．itgetsitsfood | B．itgoestochurch |
| C．itsingsintheforest | D．itreachesintobees'nests |
| A．WildBees | B．WaxandHoney |
| C．BeekeepinginAfrica | D．Honey-Lover'sHelper |
A magnifying glass |
Reth liked to study ants. He could sit for hours watching thin lines of tiny ants march back and forth. He kept a notebook, pencil, and magnifying glass with him so he could watch the ants closely and keep notes.
The magnifying glass was a great tool. With it, Reth could see the ants’ antennae wave as they marched along. He did not keep the glass on the ants for too long, though. It focused the sunlight and could burn the ants. Reth took a quick look through the glass. Then he scribbled notes. He wrote down what the ants looked like and what they did.
When Reth had enough notes, he went home and looked in his encyclopedia. It told about all kinds of ants, from army ants to fire ants. He compared his notes with the descriptions of ants in the text. Since Reth lived in a suburb, he mostly saw common garden ants. Sometimes he saw carpenter ants. He hoped to travel to the jungle one day so he could see giant Amazon ants, farmer ants, and army ants.
One afternoon Reth found a boy named Henry near the anthill. Henry was poking(戳) at the ants with a long stick.
“Why are you doing that?” Reth asked.
“I like to watch them scurry(急赶) around,” Henry replied.
“If you disturb the ants,” Reth said, “they won’t be able to get the food they need to their nest.”
“So what?” Henry asked.
Reth explained to Henry that ants collected food for their young and the queen, who were unable to leave the nest. He also let Henry look through his magnifying glass. Then he let Henry read his notes.
“Ants are like little people!” Henry exclaimed. Reth took Henry to his house and showed him the encyclopedia.
“These army ants sound really cool,” Henry said. He and Reth talked about going to the jungle to see different kinds of ants. From that day on, Reth and Henry watched the ants together, and Henry had a new respect for the hard-working insects.
1. Which word best describes Reth?| A．Rude. | B．Shy. | C．Curious. | D．Fearful. |
| A．Near Reth’s home. | B．At Henry’s house. | C．In the jungle. | D．Near the Amazon. |
| A．Two boys enjoy watching ants march around. |
| B．Two boys plan to go to the jungle to study ants. |
| C．A boy watches farmer ants and army ants through a magnifying glass. |
| D．One boy enjoys studying ants and helps a friend understand them better. |
| A．He had seen ants in the encyclopedia, and then he finally saw them in his yard. |
| B．He didn’t like ants at first, but he learned about them and became more interested. |
| C．He thought ants were interesting at first, and then he thought they were like silly people. |
| D．He loved watching ants at first, but then he became bored and decided to do something else. |
came from Europe.They had dandelion seeds on their clothes. The seeds fell from their clothes onto the ground. Since then, dandelions have spread all over.
Most people believe that dandelions are weeds. They do not want them in their gardens. But some people think that dandelion flowers are pretty. And others think that dandelions taste good. They cook dandelion leaves or put them into a fresh salad. The leaves must be picked before the flowers come out or they will not taste good. Some people make dandelion flowers into wine.
Dandelions do not die easily. If the winter is not very cold, their leaves may stay green.
When the spring arrives, their flowers come out. Each night their bright yellow flowers close
up. When the sun shines the next day, they open up again. Dandelion flowers are very unusual. They do not have to get pollen (花粉) from another dandelion flower in order to form seeds. So after several days, the yellow flower turns white and soft. A tiny brown seed forms at the bottom of each white petal (花瓣). When the wind blows, the petals float away.
Each white petal carries a seed away. This lets the dandelions spread their seeds all over.
New dandelions grow where the seeds land.
1. The underlined word “weeds” means .
| A．pretty flowers | B．fresh vegetables | C．wild plants | D．green trees |
| A．After their flowers come out. | B．After their flowers turn white. |
| C．Before their flowers come out. | D．Before their flowers close up. |
| A．The History of Dandelions | B．Dandelions: Flowers or Food |
| C．The Use of Dandelions | D．How to Grow Dandelions |
1. It is the best medicine to drink two glasses of water in the morning.
2. Drink clean water.
3. Drink the water that has not been boiled.
Many people think boiled water is safe and good to people’s health. In fact, it is not true. The boiling point of water is 100℃. By boiling it, most bacteria（细菌）in water can be killed. In the past, the water was less polluted. So boiling was a good way to make clean water. But heavy metals and other dangerous things in today’s water are much more terrible than bacteria. Boiling doesn’t fix that problem. And boiling water may give us more of the dangerous things in our glass.
4. Never use soft drinks to take the place of water.
5. Water is also needed in winter.
6. Drink water at the right time.
1) After getting up in the morning, you have less water in your body, because you weren’t drinking for the whole night. So you should drink some water to keep your health after getting up in the morning. That can prevent high blood pressure, cerebral hemorrhages（脑溢血）and so on.
2) Drinking water at about 10 am helps your body keep enough water.
3) Drinking water at about 3 pm can clean out the wastes in your body.
4) About eight o’clock in the evening is the best time to drink water. Your blood gets thicker when you sleep. Water will make your blood less thick.
Besides, we should drink 2L of water every day. Water is so important for our life. We should drink water often.
1. According to the passage, in the morning is the best .
| A．drinking some hot soup, medicine | B．drinking some porridge, breakfast |
| C．drinking some water, medicine | D．Drinking some soft drinks, medicine |
| A．Drinking some water after getting up in the morning |
| B．Drinking some water before going to bed |
| C．Drinking some soft drinks after getting up |
| D．Drinking some milk before going to bed |
| A．oil | B．food | C．wastes | D．fat |
| A．about eight o’clock in the morning | B．about eight o’clock in the evening |
| C．before supper | D．at night |
| A．Drink clean water | B．Don’t drink the boiled water |
| C．The use of water | D．Scientific water drinking |
【推荐2】On May 17, 2019 China launched a new satellite at the Xichang Satellite Launch Center（西昌卫星发射中心）. It was the forty-fifth Beidou satellite that China had sent into space.
So what is Beidou?
Beidou is a Satellite Navigation（satnav）system（卫星定位系统）. It is developed by China. The first satnav system is GPS, which belongs to the United States. GPS is the world's leading satnav system. But China's Beidou has overtaken（超过）GPS in size. China is the third country in the world to have its own satnav system, after the United States and Russia. With Beidou, China no longer has to depend on foreign systems. This is very important for national safety. As of right now, over 30 countries in Africa and the Middle East are using the Beidou system.
Work on Beidou began in 1994. However, the first two Beidou satellites were not sent into space until 2000. Since then, China has launched many Beidou satellites. These satellites have set up a worldwide network. Now, China is further improving the system. It plans to launch ten more Beidou satellites. If all goes well, Beidou will be completed by the end of 2020. The completed Beidou will be more powerful than any existing（现存的）satnav system.
Beidou has brought many advantages to our lives. In Shanghai, thousands of buses have been using Beidou. When we are waiting for a bus, we can know when it is about to come. Many smart phones have also been using Beidou. "Many people say' Let me turn on my GPS. 'In fact, their phones are using Beidou, "jokes a salesperson in Beijing. At the newly-built Beijing Daxing International Airport, Beidou has been used to do a lot of work.
根据短文内容, 选择最佳答案。
1. According to the article, how many countries had developed their own satnav systems before China?
| A．Two. | B．Three. | C．Forty-four. |
| A．26 days. | B．6 years. | C．6 months. |
| A．35 | B．45 | C．55 |
| A．America | B．Russia | C．China |
| A．Beidou depends on GPS. | B．Many people have been using Beidou. | C．GPS can be more powerful than Beidou. |
We usually go to see a doctor when we are ill. Doctors may give us some medicine.
But sometimes the medicine doesn’t work. This happened to one man, Thomas Smith. He was ill in hospital, but he wasn’t getting well. Then he found a new “doctor” inside himself. He saw funny films.
Another man, Simon Beck, was also ill, and he had a serious pain in his back. The doctor couldn’t stop it, so the man began to “picture” his pain.
| A．He read funny books. |
| B．He wrote his story in his book. |
| C．Reading is good for everyone. |
| D．These stories may surprise you. |
| E．In his head, he drew a picture of a dog. |
| F．The medicine often makes us feel better. |
| G．We need to do more exercise to keep us healthy. |
In Chinese culture, it is believed that people with fair skin are more beautiful. However, in Western culture, many people think tanned skin is prettier. The example shows that different cultures have different ideas of what is beautiful. These cultural meanings of beauty, however, are no longer important. As more and more people travel overseas, ideas about beauty are being shared. The Internet has also made it easier for people to share different types of beauty. The result is an ever-changing idea of what is beautiful.
The cultural practice of ear piercings (打耳洞), for example, has become a part of modern day culture. In Kenya, it is a tradition among the Masai men and women to pierce and then make their ear lobes (耳垂) longer using wood or stones. They then wear colorful things on their ear lobes. This is a common practice since longer ear lobes are seen as a sign of beauty. This tradition has now found its way into present-day culture. Nowadays, this might still seem unusual to some, but with more and more well-known actors and film stars showing off their longer ear lobes, it will finally become more fashionable.
It is understood that different cultures around the world have different ways of showing beauty. However, since we now live in a worldwide society, people’s views about beauty are always changing. With the help of the Internet, people are now able to easily borrow ideas from other cultures to help them stand out. So what new fashions can we expect to see in the future?
1. What has made it easier for people to share ideas about beauty?| A．Internet. | B．Fashion. | C．Culture. | D．Tradition. |
| A．Longer ear lobes are their new fashion. | B．Only women make their ear lobes longer. |
| C．They think longer ear lobes look beautiful. | D．They make actors and film stars famous. |
| A．people | B．ideas | C．cultures | D．fashions |
| A．People in Asian countries like fair skin better. |
| B．Beauty is considered important in many cultures. |
| C．Different cultures have different ideas about beauty. |
| D．People’s ideas about beauty are changing all the time. |
In the year of 2020, China’s Ministry of Education began to ask all public schools to teach students first aid(急救) especially CPR as part of children’s health education. There are as many as 550,000 sudden cardiac(心脏的) deaths in China every year. About 60% of these deaths happen outside hospitals and the survival rate(存活率) of a patient who received the CPR outside hospital is less than 4.5% in China, compared with about 47.5% in developed countries.
In November 2019, in Taiwan Province, 35-year-old model-actor Godfrey Gao died after he suddenly fell while filming a reality show. He was rushed to the hospital and died from sudden cardiac arrest(骤停) after being rescued for nearly three hours. His death aroused(引起) a heated discussion.
Sudden cardiac death is increasing year by year due to many reasons. CPR is one of the first and most effective ways of treating cardiac arrest, according to medical experts. Most patients will begin to develop brain in damage(损伤) within four to six minutes after cardiac arrest, and then biological death within a few minutes. However, in China, besides medical workers if people who have received first aid training is only about 1% of the public.
As early as 1966, the US has advised the public to receive CPR training, including police officers, drivers, firefighters, teachers and students of colleges and high schools. In Europe, Switzerland requires all citizens(公民) to be trained in first aid, including CPR. And in Germany, every citizen must be trained before getting their driver’s license, which means about 80% of the country has received first aid training. 40% of people in France are also trained in first aid.
According to Guo Malong, a doctor in Henan, a CPR lesson can be completed in anything from 45 minutes to 2 hours depending on what’s included. Basic first aid lessons can be completed in just 30 minutes, which don’t cost students too much time, but will make a huge difference to others.
根据短文内容，判断正误（T / F）。
1. About 530,000 sudden cardiac deaths happen outside hospital in our country every year.
2. The writer mentions Godfrey Gao in order to show how dangerous sudden cardiac arrest is.
3. All students including high schools must receive CPR training in the US.
4. Every driver is trained in first aid in Germany.
5. In the last paragraph, Guo Malong’s words mean it is easy and possible to teach CPR in school.
【推荐3】One of the most popular types of fishing in Scandinavia, Russia and Germany is ice fishing. It’s also a popular sport in Canada and the United States. People can even go ice fishing all year round in Alaska. The sport was brought to America by Swedish, Norwegian and Finnish settlers(移民)who came to Minnesota, a state where people are interested in this sport. Ice fishing was introduced to Canada from Minnesota, and from there to Alaska.
Ice fishing requires people to catch fish with lines, hooks(钩子)and other tools through a hole in a frozen lake. They can sit in a warm cabin on the ice over the hole, or stand in the freezing open air.
Of all the types of fishing, ice fishing may require the least effort and skill, just patience and luck. Followers of this sport won’t be afraid of staying on ice even at very low temperatures. It’s not for everyone, and of course people in warm countries have no chance to fish this way, while many people in the north take ice fishing very seriously, and they even have ice-fishing competitions. The winners can receive good prizes. At the very least, ice fishing can be a fun way to break up those cold, dull winter days, and get a taste of the open air.
1. In Alaska, people can go ice fishing ________.| A．only in winter | B．after they built a cabin |
| C．at any time of the year | D．when there is a competition |
| A．Russia | B．Alaska | C．Germany | D．Minnesota |
| A．have your own cabin | B．practice for a long time |
| C．be patient and healthy | D．be skillful at fishing |
| A．Standing on the ice is a healthy way of exercise. |
| B．People can go ice fishing in any part of the world. |
| C．People can get good prizes. |
| D．People can have fun and enjoy the open air. |
| A．A Popular Sport | B．Go Ice Fishing |
| C．Types of Fishing | D．Stay on Ice |
【推荐1】I walked into a restaurant and ordered some food. After about 20 minutes, a large group of people came in and placed their own orders.
To my disappointment, the group got served before me. I watched as they began to eat and laugh heartily. I heard one of them bragging (吹嘘) about how he’d connected to someone who worked at the restaurant. Unable to stand it anymore, I decided to leave. I called the waiter over to cancel my order.
He calmly told me, “Yours is a special order being prepared by the head chef himself. It’ll take a little more time. Please have a drink while you wait.”
I calmed down and waited patiently. Shortly after, my meal was served by six waiters.
To my surprise, the owner of the restaurant turned out to be a long-lost friend of mine. He had seen me as I walked in and decided to surprise me. He upgraded (升级) my simple meal to a five- star meal for free. The people at the other table were shocked and couldn’t stop staring. Suddenly they started murmuring (低声抱怨 ), asking why they didn’t get that kind of service.
Such is life! Some people are ahead of you, laughing at you and talking about how they are smarter, wiser and better than you, how they are well-connected and blessed (幸运的 ). You are working hard tirelessly,wondering why it’s taking so long for you to be rewarded.
You just have to wait longer because your reward (回报) is more special.
1. The author wanted to cancel his order because ________.| A．he ordered the wrong food | B．the restaurant was too noisy |
| C．a group of people laughed at him | D．people who came after him got served first |
| A．forgotten by the waiter | B．a special treat from an old friend |
| C．served to the other table purposely | D．less tasty than he thought it would be |
| A．bored, glad | B．lucky, excited | C．angry, surprised | D．shocked, unhappy |
| A．Wait Patiently for a Rewarding Life | B．Meet My Long-lost Friend Again |
| C．Laugh at Other Unlucky Guests | D．Have an Unhappy Experience |
【推荐2】The idea may hit you once or twice a year. You come home on a hot summer day, hoping to have a cool bath, and find there is no water. Then you see how important water is in your everyday life. However, in many parts of the world, water is not just about one’s everyday needs.
In countries like Tanzania, water is hard to get, and the job of collecting water falls on women’s shoulders. Girls are often kept home from school to collect water while their brothers stay at school studying. Studies show Tanzanian girls who live 15 minutes away from clean water spend 12% more time at school than those who live an hour away. More time spent collecting water means less time for learning. For these girls, “Knowledge is Power” is not just words; it is a sad fact in real life. With less time spent at school, their chances of getting well paid jobs are small, and they often have no voice on important matters, like who to marry. These girls are often married into poor families. They have little money or knowledge to take care of their children，who often end up dying young. For the baby girls who are lucky enough to survive，their life may still center around “water，"just like their mothers'.
1. What does the underlined part “The idea" refer to？| A．Water is important in one's everyday life. |
| B．Water is not just about one's everyday needs. |
| C．It is nice to have a cool bath on a hot summer day. |
| D．We should not take a bath when there is a little water. |
| A．must collect more water | B．will marry into rich families |
| C．may have more time to study | D．can understand “Knowledge is Power” |
| A．children in poor countries die from drinking water every day. |
| B．children from poor families stay at home and care for younger children. |
| C．Tanzanian girls are often paid less for the same job than the boys are. |
| D．Tanzanian girls with little education can hardly have a bright future |
A． | B． | C． | D． |
| A．Why it is important to save water. | B．Why it is hard to get water in poor countries. |
| C．How water may play a part in one’s future. | D．How water may give a country power. |
Maybe you are right. After you leave school, it’s necessary for you to understand such things. Please remember that at school, besides getting knowledge, you should pay attention to some other important things.
First, try to find what you are most interested in. At school, you study many subjects. Try to find which you like and which you don’t like. This may be helpful to you in the future. Second, maybe you don’t like math and you want to drop it. But the logical thinking ability from math can help you solve some problems. At school, you should practice your brain by thinking. Third, you should believe in yourself. Maybe you learn English at school, but you don’t need to speak English in your daily life at all. You should think learning English can prove that you have the ability of learning languages. Suppose you go to France one day and find a job there. Then you can tell yourself, “I can do my job well. At school I learned English well, and now I must be able to learn French well, too.” But if you have no confidence, what will happen?
Try to challenge yourself as often as possible. I think many of us like playing computer games. When we fail in a game, we always want to try it again. Why? Because we want to get the highest marks, though it is hard for us to get it. If we want to challenge ourselves, we must face more difficult things and make greatest progress.
1. At school you should _________.
| A．study math harder than any other subject |
| B．stop learning the subjects you don’t like |
| C．not only get knowledge but also improve your ability |
| D．pay mor e attention to math |
| A．ability of learning languages |
| B．ability of finding a job |
| C．interest in other subjects |
| D．ability of logical thinking |
| A．You’ll use everything you learn at school in the future |
| B．It’s not necessary to know what you like at school. |
| C．Everything you learn at school has some influence on you |
| D．Logical thinking ability is the most important ability |
| A．have confidence in learning languages |
| B．go to France |
| C．study in a good school |
| D．get a good result in the exam. |
| A．everyone loves to play computer games |
| B．it is not easy to get high marks in computer games |
| C．we should do some very difficult things |
| D．we should challenge ourselves. |
