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Scientists have invented a new way to make electricity. Humidity( 湿气) in the air is what helps create the electricity. Since the new device generates electricity from the air, the scientists call it "Air gen".

The new device is very small and very simple. In it. water molecules from the air move through tiny holes from the upper part of a material down into the lower part of the material. The holes are the key. The material has lots of teeny- tiny holes called"nanopores", which are 100 nanormeters(纳米) across. That's about l. 000 times thinner than the width of a human hair. As the water molecules work their way through the nanopores, they upset the electrical balance between the upper and lower parts of the material, leaving the upper part with a greater charge. This "imbalance" between the two parts is what creates the electricity.

Currently. the device only makes a small amount of electricity- enough to power a small sensor. But in lab tests. the Air gen. which is a little bigger than n fingernail, produced that electricity all day and all night for a week, powered by nothing but the air.

Scientists have tried to make electricity from humidity before, but those methods didn't work for long. or were expensive to make. But in 2020，Dr. Yao and his team found a way of getting electricity from humidity using special "nanowires" made from bacteria and later made the key discovery of the Air-gen: almost any material can create electricity in this way as long as it has nanopores of the right size.

They are hopeful that the Air gen will become an important green energy source. But some scientists have suggested that it might be hard for the Air-gen to create enough electricity to really make a difference- especially compared to power sources like solar energy.

Because the device so thin, Dr. Yao and his team believe that many Air -gen layers could be piled on top of each other to create more electricity without taking up more space. Dr. Yao says, "What I envision is that sometime in the future, we can get clean electricity wherever we go.'

For the first time, astronomers have caught a star in the act of eating a planet. The star. known as ZTF SLRN-2020，exists approximately 12 ,000 light -years away in our galaxy. 

"For decades. we've been able to see the before and after," says study leader Kishalay De. "Before，when the planets are still orbiting very close to their star, and after. when a planet has already been swallowed up, and the star is giant. What we were missing was catching the star in the act， where you have a planet going through this fate in real-time. That's what makes this discovery really exciting. "

In 2020，De was studying data, hoping to find evidence of two stars combining with each other. This usually results in bursts of light thousands of times brighter than the stars themselves. But one shining star De discovered was much dimmer(黯淡的)，only 100 times brighter. Also, the crash of two stars usually produces hot gas. However, this one was surrounded by dust molecules(分子). De wondered if he had detected a star swallowing a planet.

He and his team spent the next two years examining similar data. NASA provided the final piece of evidence they needed. The images allowed them to confirm that the molecules were traces of a star eating its planet. The scientists said that as the planet was being swallowed. it  displaced hot gas from the star. The gas then cooled and created dust. Pieces of the planet also blew away from the star, producing more dust.

Some scientists believe Earth will also be consumed by the Sun in about five billion years. But Mansi Kasliwal, a professor, says humans will not be around then. The increasing heat from the expanding Sun will evaporate(使蒸发) all the water from Earth long before it gets close enough to swallow it, making it uninhabitable. Smadar Naoz, an astronomer, agrees that the Earth's water sources will dry up."Whether or not the Sun will swallow the Earth is quite controversial," she says."But it wouldn't matter because it will no longer be our beautiful. Earth with an atmosphere and oceans."

I was living with my grandparents at the time. Our grandparents had recently retired. While they'd managed to save enough to buy a home, they were short on living expenses. 

So, our grandfather took a job as doorkeeper of the Java school building. Keeping the entire building clean was a stressful job for one man, Realizing this, 1 began helping him after school, sweeping rooms and emptying waste baskets, for a small wage.

When winter arrived, he fired up the school's furnace(火炉). He quickly realized how difficult it had become for him to shovel(铲) the huge pile of coal chips required to fill in the furnace. I volunteered to take on that job， a commitment that required me to set my alarm clock an hour earlier each morning. I'd go over to the school, and shovel a half ton of coal, enough to keep the fire burning for 24 hours. After finishing that task, I'd go home, change clothes, and eat breakfast. Then I'd head back to school, always at the last minute.

It was during those morning rushes to school that I discovered my superpower. On two mornings, at the very instant I stepped onto the sidewalk in front of the school, the first bell rang. That was the signal for students to head to class. This astonishing coincidence caused me to improve my precision. I carefully planned each phase of my morning activity. I paced myself. Often I'd step onto the school's sidewalk just as the first bell rang. This accomplishment gave me enormous pride- and some strange feelings.

Decades later, at a school reunion, I happened to meet Harold Spiry, who had been in charge of ringing the bell by pressing a button in his office. I couldn't resist boasting(吹噓). I told Mr. Spiry about how well I had ordered my complex morning work back then, how my timing had been faultless. "Oh that," he said,"Do you recall that my office windows looked out over the front of the building? I often saw you coming. And when you hit the sidewalk, I'd ring the bell.

National Museum of Natural History

FIRST FLOOR | EXHIBIT

African Bush Elephant

Learn about the ecology of African elephants, their place in geologic time, and their connections to humans.

Things to Do:

Feel"elephant voices" the low-frequency voices that elephants use to communicate over distances as long as 10 miles.

Watch a short film of African bush elephants in action,

Learn why elephants are called"ecosystem engineers".

SECOND FLOOR| TEMPORARY EXHIBIT

Lights Out : Recovering Our Night Sky

Experience the grandness of a starry night，discover the dark side of artificial lights, and find out how you can reduce light pollution and reconnect with the night sky.

Things to Do:

Look through a"telescope"into the past, adjust the sky-glow in a famous painting, and see how artificial lights affect mating fireflies.

Find dark-sky sites around the world- there may be one near you!

FIRST FLOOR| TEMPORARY EXHIBIT

Sea Monsters Unearthed: Life in Angola's Ancient Seas

Get up close to the fossil remains of giant reptiles -mosasaurs (沧龙) and sea turtles that once ruled the sea off the coast of West Africa 88- 66 million years ago. .

Things to Do:

Touch the teeth of a shell-crushing mosasaur.

Compare Angola's ancient ocean ecosystems with today' s in a spinner interactive.

Take a photo of yourself with a massive mosasaur that' s ready to bite.

SECOND FLOOR| EXPERIENCE

The Garden Lounge

Relax and recharge among an indoor garden of live plants.

Things to Do:

Play a sliding-door interactive game to learn how seeds spread.

Charge your mobile device.

Relax，breathe in deeply and sit for a while!

Long long ago，there was a big apple tree. A little boy loved to come and play around it every day. He climbed to the top of the tree，ate the apples，and took a nap under the shadow. He loved the tree and the tree also enjoyed playing with him.

As time went by，the little boy grew up and he no longer played around the tree.

One day，the boy came back to the tree，appearing sad."Come and play with me，" the tree asked the boy gently.

"I am no longer a kid；I won't play around trees anymore，"the boy replied."I want toys. I need money to buy them."

"Sorry，but I don't have money. However，you can pick all my apples and sell them. Then，you will have money."The boy was so excited that he picked all the apples on the tree and left happily. The boy didn't come back after that.

The tree was upset.

One day，the boy returned and the tree was so joyful."Come and play with me，" the tree said.

"I don't have time to play. I have to work for my family. We need a house for shelter. Can you help me？""Sorry，I don't have a house. But you can cut off my branches to build your house."So the boy cut all the branches of the tree and left with delight.

The tree was glad to see him happy but the boy didn't appear since then. The tree was again lonely and sad.

One hot summer day，the boy returned and the tree was delighted."Come and play with me！"the tree requested.

"I am sad and becoming old. I want to go sailing to relax myself. Can you give me a boat？""Use my trunk to build the boat. You can sail and be happy."So the boy cut the tree trunk to make a boat. He went sailing and did not show up for a long time.

注意：1. 续写词数应为150左右；
2. 请按如下格式作答。

Paragraph 1：

Many years later, the boy finally returned. 

Paragraph 2：

The apple tree is our mother.

注意：
1.写作词数应为80左右；
2. 可以适当增加细节，以使行文连贯。

The earliest memory I have of my father is one of me as a young boy holding his hand by his two last fingers as we walked together.

As I grew older I remember us listening over a radio to high school ball games together. I would1 how many points each player would score as the game went on. Too small to stay awake for the2 game, I always fell asleep3 the game ended. But the next morning I would find by my pillow the score sheet filled out with the 4 score on; it was 5 by my father.

In high school，I became very interested in athletics. My father would6 all my games. Good 7 in my senior year entitled our football team to the state championship game. The night before, my father 8 announced he had to 9 the bread to the stores and the site of the games was a three－hour drive from his route. Back then I wasn't fully noticing his 10 . 

The next day as game time approached I couldn't help thinking about Dad. Suddenly, I saw a bread truck pulling into the stadium. 11 completed, he made the long drive in time to at least see 12 of my championship game.

Years later, I was awakened early one morning by a ring at 5：30 A. M. As I 13 to answer the phone, I'll never forget the sound of the sheriff's voice—my dad had just been killed in an automobile accident on his way to work. It felt as if my heart had been torn away.

For long I tried to remain strong14 it and pretended I didn't care until one day in the playground a little boy walked up to me and grabbed my hand by my last two fingers. I completely lost it—I just let go and cried. And I felt a sense of15 . Sometimes you just have to cry and there's no need to hold back anymore.

How to Protect Wildlife

Wildlife faces threats from habitat destruction, pollution, and other human actions. Although protecting wildlife may seem too hard at times, even small actions can help protect many different animals. 

● Create wildlife friendly areas. When trying to make your garden more beautiful, choose plants that can provide food and shelter to native wildlife. This will also help cut down on pollution. 

● By using less water and fewer fuels, you will be helping to protect the wildlife around you. Take buses or the subway when you can and turn off electric devices when you're not using them.

●Buy products that are wildlife－friendly.  Keep in mind that some endangered animals are killed by traps, catches or hunters who are after other wildlife within the same habitat.

●Limit family size. Population growth is one of the major factors in habitat destruction. With the rapidly growing population, more and more habitats for wildlife are occupied by humans.  In this way, the Earth's population will stabilize and native habitats can be protected.

A .Live a greener life.

B. Donate money to organizations.

C. Each family should be limited to one or two children.

D. Avoid products that are made from endangered animals.

E. Protecting wildlife from being endangered is every family's duty.

F. Here are some tips on how to protect wildlife through small actions.

G. Build bird houses to your garden or yard to attract and shelter these species.

As I stuck in the mud (泥), with my bike on top of me, I wondered what had forced me to come here. Madagascar is not a good place for a cycling holiday: one of the world's poorest countries, only 11 percent of roadway is paved (铺). South of the town of Antalaha, where I started, the road was in worse condition.

I appeared from a week in the wilderness and reached the start of the Route National 5 at Maroantsetra, but my dream of a smooth road and speed was suddenly destroyed by mud.The "worst road in the country" changed my bicycle into a burden (负担) for days. Finally, I was claimed by the road. Tired. Alone.

As I wiped (擦) the mud from my face and looked upwards, I was greeted by a Malagasy man. He helped me stand up and smiled playfully while he pointed to my bike, which sat next to his. I started again. But I fell again in the mud. Angrily, I told him to go on, but if he understood he showed no sign of it. His smile forced me back onto the bike. We continued like this for hours. But I fell less. Studying my quick guide, slowly I learned. As we passed through a village, a group of children saw me and shouted loudly. His only words were: "Their parents tell them while people steal and eat them. Funny, no？"

I tried to ask why, but he had already set off. I tried to catch up; as I got closer, he took it as a challenge and sped up. We raced along the road. I rode a little faster and I was just behind, about to catch up with him. With a smile, he sped up and was away, leaving me breathless.

Human beings have used tools for a very long time. In some parts of the world you can still find tools that people used more than two million years ago. They made these tools by hitting one stone against another. In this way, they broke off pieces from one of the stones. These chips of stone were usually sharp on one side. People used them for cutting meat and skin from dead animals, and also for making other tools out of wood. Human beings needed to use tools because they did not have sharp teeth like other meat－eating animals, such as lions and tigers. Tools helped people to get food more easily.

Working with tools also helped to develop human intelligence. The human brain grew bigger, and human beings began to invent more and more tools and machines. The stone chip was one of the first tools that people used, and perhaps it is the most important. Some scientists say that it was the key to the success of mankind.

Since 1960 a new kind of tool has appeared. This is the silicon chip (硅芯片). It is smaller than a finger nail, but it can store lots of information. It is an electronic brain. Every year these chips get cleverer, but their size gets smaller, and their cost gets less. They are used in watches, calculators and intelligent machines that we can use in many ways. In the future we will not need to work with tools in the old way. Machines will do everything for us. People will have plenty of spare time. But what will they do with it?

Human beings used stone chips for more than two million years, but human life changed very little in that time. We have used silicon chips for only a few years, but life is changing faster every day. What will life be like twenty years from now? What will the world be like two million years from now?