On March 14, math and science lovers around the world celebrated a special day: Pi Day.

Pi is equal to about 3.14, but the number goes on endlessly. It is sometimes written in Green π. With the help of computers, mathematicians (数学家) have been able to calculate (计算) pi out to over a trillion (万亿) decimal (小数的) places, but there is still no end to the number. This makes pi confusing, even for the most famous scientists and mathematicians.

Pi Day is celebrated around the world on March 14, since how we write this date, 3/14, looks just like the number pi.

For some people, the appeal (感染力) of Pi Day goes far beyond math and science. Pi shows up throughout popular culture. You can see it in movies, comics, music and more. “In modern movies, any time the filmmaker wants to produce a sense of mystery, often the symbol pi is used,” says David Blatner, Jewish American writer of the Joy of Pi.

People also love trying to memorize the digits (数学) of pi and competing against others to see who can remember the most. Many teachers hold class contests to see how many numbers their students can memorize. The Gummess World Record for reciting the most digits of pi is held by Li Chao of China, who successfully recited pi put to nearly 67,890 decimal places.

Above all, Pi Day is about having fun with the number. People celebrate Pi Day by eating or throwing pie and with fun pi-related games and activities. This year, Princeton, new Jersey, held a Pi Event” where people walked 3.14 miles together. Just like the number itself, the possibilities for Pi Day are truly endless.

1.From the first two paragraphs, we know that ______.

A.Pi Day is on March 15 B.the number of Pi is endless

C.it’s a day just for mathematicians D.mathematicians are able to calculate pi out

2.In modern movies, the symbol pi is often used to ______.

A.represent maths and science B.describe something mysterious

C.remind us of movies and comics D.show popular cultures around the world

3.People compete against others about pi by ______.

A.eating as many pies as possible B.going for a hike for 3.14 miles.

C.remembering the most digits of pi. D.holding a birthday party for Albert Einstein

4.When people celebrate Pi Day, they may feel ______.

A.crazy B.confused C.nervous D.cheerful

In the past you could draw anything you wanted on a computer screen and then printed it out on a piece of paper—a flat piece of paper. But imagine being able to print something that is three-dimensional— 3D. Would you like to design an object, such as a cup or a toy, and then “print” it out? Well, there is the technology to help you do this—to produce even a whole house!

3D printers might be the size of a suitcase, or even a small room, depending on the object they are made to produce. You make a 3D design on your computer and send it to the printer. Inside the machine, the object you have designed is made as one object.

So how is this being used? In medicine, 3D printing is often used to make heath. The dential takes a 3D image, something like a photo of the real tooth and a new one is printed in that exact shape. Then you might also want to print a mobile phone cover or a special pair of shoes.

Scientists are taking this even further. They have made a bicycle that just needs a chain and two lyres (轮胎). Car pans (壳) have been made for a while and now they are even making a body of a whole car!

But imagine how printing a whole house might help people build houses. A Chinese company has made houses using a giant 3D printer. They use a mixture that includes concrete (混凝土) and recycled building waste. This is a good thing as it helps the environment. They believe that their method of printing houses is cheaper, faster, less dusty and less noisy than the ordinary(普通的) way that houses are built.

It seems that 3D printing technology will change our world, and China is leading the way.

1.The size of a 3D printer might be ______ according to the object they design.

A.changeable B.always small C.seldom big D.the same

2.In medicine, 3D printing is often used to print ______ in the exact shapes.

A.dentists B.teeth C.photos D.mobile phone covers

3.Scientists are taking this even further. Here “this” probably means ______.

A.a pair of shoes B.a whole car C.a new bicycle D.the printing

4.The passage is mainly about ______.

A.the introduction to 3D technology B.the advantages of 3D technology

C.the history of 3D technology D.the influence of 3D technology

Jane slammed the door of the log cabin (小木屋) raced toward the Indiana woods. Mother and Father insited that Jane go to school and learn to read. It was September of 1825, and Jane wanted to help on the farm like her brothers. Therefore, she told her parents “No!” and refused to learn to read.

Jane scooped (捧起) up her long skirts and splashed (溅起水花) through a small stream. Running helped her collect her thoughts, so she ran for what seemed like hours. She dashed around a tree and wasn’t paying attention. As a result, she tripped (绊倒) over a pair of long legs stretched out in the grass.

The legs belonged to her neighbor, Abe Lincoln. Abe was leaning (斜靠) against a tree reading a book. He smiled, stood up, and extended his arm to help Jane up.

Jane recognized Abe and knew what a hard-worker he was. But she also heard he was not like the other sixteen-year-old boys in Perry County. Abe was different because he spent all of his spare time reading books.

“Why are you running so fast?” Abe asked. “Are you hurt?”

Jane frowned (皱眉). “No, I’m all right,” she said. “I’m running because I’m upset. My parents want me to learn to read, and I told them no!”

Abe looked down at his book and then at Jane. “Reading can change your life,” he said quietly. Meet me here tomorrow, and I’ll prove to you how important reading is.”

Jane met Abe the next afternoon. He showed her a book about George Washington. One of his favourite teachers had donated it to him, and he had read it many times.

Abe began to read aloud while Jane listened carefully. He read about Washington and what a great leader he was. He read about Washington’s courage and bravery.

“Someday I want to be as courageous as George Washington,” said Abe proudly. “Someday I will be president of the United States, too.”

“I believe you will make a great president,” said Jane. “Look at what a good leader you are now. You’ve completely changed my mind about reading!”

Years later, Jane opened her newspaper and read the good news. Her friend, Abe Lincoln, had an elected President of the United States. She smiled and thought about the day she tripped over long legs. That was the day that changed her life.

1.Instead of going to school, Jane preferred to _______.

A.teach herself by reading books B.run through the Indiana woods

C.give a helping hand to her family D.play with her neighbor Abe Lincoln

2.Jane changed her mind about reading, because ______.

A.Abe shared the book and thoughts B.Abe’s teacher donated a book

C.Jane’s parents forced her to study D.Jane tripped over Abe’s long legs

3.From the passage, we can see Abe is _______.

A.strict and quiet B.generous and creative

C.confident and humorous D.helpful and hard-working

4.The passage is probably from ______.

A.a novel B.a guide C.a poem D.an advertisement

阅读下面短文,根据所读内容,在文章后小题的空格里入一个最恰当的单词,并将答案填写在相应位置上。注意:每个空格只填1个单词。

A rain forest gets huge amounts of rain. That’s why it’s called a rain forest! More than 100 inches of rain fall there each year. In contrast, Los Angeles, California, gets only about 15 inches of rain per year.

Rain Forest Plants and Animals

A rain forest has hundreds of kinds of trees and flowers. Under your feet is a carpet of leaves.Moisture (水气) is dripping everywhere. Hardly any light reaches the ground because tall trees form a canopy (树冠), or upper layer, high above. It hides the sky and provides shade.

A rain forest is noisy! Bird squawk. Thousands of insects buzz and hum. Monkeys chatter in the trees. Beetles grow as big as your hand. Some frogs grow as big as a milk carton!

Why Are Rain Forest in Trouble?

Rain forests are very important to life on Earth. They recycle. Tree roots use dead plants as food. Rain turns into clouds that make more rain. Trees take in carbon dioxide (二氧化碳) and gives off the air we breathe.

Yet rain forests are in trouble. People cut down trees to get wood and land to farm. Most trees are not replaced. Many scientists think this may be a cause of global warming. Loggers also may leave rubbish behind. This is a kind of pollution.

The balance of life in a rain forest is complicated (复杂的). Plants and animals depend on one another. If one dies out, others do, too.

The Children’s Rain Forest

Children in a Swedish school were studying rain forests. They learned that rain forests were in trouble. The class stated a project to save a rain forest in Costa Rica. The class bought about 15 acres of land. They paid 525 per acre. The students hoped that the land they bought would be protected and not destroyed.

The students became so interested in rain forests that they decided to get a closer look at areal river. They saw alligators (短吻鳄) crocodiles. A guide took Myers and his students into the rain forest. “The monkeys were not happy that we were in their forest. They broke small branches on the trees and threw them at as.” One of the students said. “It was a great learning experience for all of us,” said Myers. This was the start of the children’s Rain Forest. This project works to save rain forest all over the world.

Tide: Rain Forest

Introduction

·Because of a great deal of rain, the rain forest gets its1..

·Compared with the rain fall in Los Angeles, the rain fall in the rain forest gets over2. times the amount of rain per year.

Wildlife in rain forests

·With tall trees hiding the sky, the forest is very 3. and wet.

·Many animals like birds, insects and monkeys make a lot of noise.

·Beetles and frogs are much 4. than the ones we usually see.

Rain forests in

5.

Rain forests are of great6. to life on Earth by recycling.

·People cut down trees to get wood and land to farm.

·Scientists believe it may cause global warming.

·The rubbish which is left behind also 7. rain forests.

·Plants and animals have a close 8. . One dies out and others do, too.

The Children’s Rain Forest

·Children in a Swedish school started a project by 9. 15 acres of land.

·The monkeys in the rain forest were 10. about their arrival.

·This project works to save rain forest around the world.

根据短文内容和首字母提示,填写所缺单词,并将答案填写在相应位置上。

Praised as “the goddess scientist”, Ning Yan, 42, is a leading biology researcher at Princeton University in the US. You may not know Yan’s contribution to biology, buy she is a rising s 1.in the science world and her resume (简历) is impressive. After graduating from Tsinghua University and Princeton, she was invited to set up her own lab at Tsinghua in 2007. At age 30, she became one of China’s y 2. female professors. It was a long road to get w3. she is now. She always believes that scientists need so have a pare mind and perseverance (毅力).

Yan likes to work at night. She says it’s because she can focus when the outside isq4. , She also works at least 14 hours a day, h5.she’s energetic, because researchis the most “comfortable job for her. Her devotion to her work probably h 6. Yan to her research to find the structures of proteins (蛋白质) in cells’ Plasma membranes (细胞质膜) in 2016. All her a 7.got her listed among the journal Nature’s Science Stars of China (中国科学之星).

Besides scientific research, Yan enjoys TV dramas and classic novels. Surprisingly, the novel Journey to the West inspired her to become structural biologist. In the book the Monkey King can change into many o 8. animals. She wondered what it would be like to change herself.L9.. Yan now lives in that world every day, exploring how proteins, work at the level of atoms. “It was almost destined (注定的) that I would become a structural biologist,” she said in an interview with Nature.

As she realizes her own dreams, Yan tries to e 10. more women to persue careers in science. In her eyes, there is no difference between men and women in the scientists fields.

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