What will power your house in the future? Nuclear, wind, or solar power? According to scientists at the Massachusetts Institute of Technology (MIT) in the US, it might be leaves – but man-made ones.
Natural leaves are able to change sunlight and water into energy. It is known as photosynthesis (光合作用). Now researchers have found a way to copy this seemingly simple process.
The man-made leaf developed by Daniel Nocera and his partners at MIT can be seen as a special chip with catalysts (催化剂). Similar to natural leaves, it can split water into hydrogen and oxygen when put into a bucket of water. The hydrogen and oxygen gases are then stored in a fuel cell (电池), which uses those two materials to produce electricity.
A man-made leaf is not a new idea. The first man-made leaf was invented in 1997 but was too expensive and changeable for practical use. The new leaf, on the contrary, is made of cheap materials, easy to use and highly stable. In laboratory studies, Nocera showed that a man-made leaf prototype (原型) could operate continuously for at least 45 hours without a drop in activity.
The wonderful improvements come from Nocera’s recent discovery of several powerful, new, inexpensive catalysts. These catalysts make the energy change inside the leaf more efficient with water and sunlight. Right now, the new leaf is about 10 times more efficient at carrying out photosynthesis than a natural one. Besides, the machine can run in whatever water is available; that is, it doesn’t need pure water. This is important for some countries that don’t have enough pure water.
With the goal to “make each home its own power station” and “giving energy to the poor”, scientists believe that the new machine could be widely used in developing countries, especially in India and rural China.
1.What will give power to our house in the future, according to MIT?
A. Man-made leaves. B. Nuclear.
C. Solar power. D. Wind.
2.Which of the following orders correctly shows how the man-made leaf is used to produce electricity?
a. man-made leaves split water into hydrogen and oxygen
b. the hydrogen and oxygen gases are stored in a fuel cell
c. the man-made leaves are put in water
d. the fuel cell uses hydrogen and oxygen to produce electricity
A. cbad. B. bcad.
C. cabd. D. cadb.
3.What does the underlined “stable” in the 4th paragraph mean?
A. Secure. B. Powerful.
C. Unnatural. D. Unchangeable.
4.The aim of the scientists at MIT in developing the new man-made leaves is to .
A. build up more power stations in the world
B. provide cheaper energy for developing countries
C. offer people in developing countries access to pure water
D. gain a deeper understanding of the photosynthesis process
Artificial intelligence (AI) technology may soon be a useful tool for doctors. It may help them better understand and treat diseases like breast cancer in ways that were never before possible.
Rishi Rawat teaches AI at the University of Southern California’s (USC) Clinical Science Center in Los Angeles. He is part of a team of scientists who are researching how AI and machine learning can more easily recognize cancerous growths in the breast. Rawat provides information about cancer cells to a computer. He says this data helps the machine learn. “. . . You can put the data into computers and they will learn the patterns and the pattern recognition is important to making decisions.”
David Agus is another USC researcher. He says machines are not going to take the place of doctors. “Computers will not treat patients, but they will help make certain decisions and look for things that the human brain can’t recognize by itself. Once a confirmed cancerous growth is removed, doctors still have to treat the patient to reduce the risk of cancer returning. The form of treatment depends on the kind of cancer.”
Currently, researchers take a thin piece of tissue, put it on a small piece of glass and add color to better see the cells. That process could take days or even longer. Scientists say artificial intelligence can do something better than just count cells. Through machine learning, it can recognize complex patterns, or structures, and learn how the cells are organized.
The hope is that machines will soon be able to make a quick identification of cancer that is free of human mistakes. “All of a sudden, we have the computing power to really do it in real time. . . We couldn’t have done this, we didn’t have the computing power to do this several years ago, but now it’s all changed.” Agus adds that the process could be done for almost no cost in the developing world. He says that having a large amount of information about patients is important for a machine to effectively do its job in medicine.
The University of Southern California researchers are now only studying breast cancer. But doctors predict artificial intelligence will one day make a difference in all forms of cancer.
1.In Rishi Rawat’s research, ________.
A. the data put into computers contributes to cancer recognition
B. many cancers are being studied at the moment
C. machine learning has replaced doctors’ work
D. the focus is on the cure for cancer
2.David Agus’s words in Paragraph 3 are used to ________.
A. provide some advice for doctors
B. introduce the development of cancer
C. appeal to scientists to research into cancer
D. explain the function of AI in treating cancer
3.What can we infer from the text ?
A. AI can make decisions for doctors.
B. Developing countries might be lack of funds.
C. AI will hopefully make an accurate identification of cancer.
D. Computing power has long helped with the identification of cancer.
4.What is the author’s attitude towards AI used in treating cancer?
A. Positive. B. Indifferent.
C. Doubtful. D. Negative.
It is obvious that all of our childhood memories are not accidental. When you are a child, every scent, every sound, every move, every toy, the first day of school, the first kiss, the first step. . . Everything together makes what is the personality of a man. All these are pieces of one whole entity.
I was about 6 years old. My mom's best friend left to another town and asked my mom to stay at her place with me for two days in order to look after her two sons. One was a little older than I was. and the second boy appeared to be super grown-up, for he was already fourteen. I always enjoyed staying at their place.
I remember the second day we were supposed to have the come-back party for my mom's friend at her place. I woke up. Mom went to work and reminded me to be nice and clean by the time she came back. I stayed with Tony, the older of the boys and suddenly somebody called him and though he was not permitted to leave me alone-he left. He said it would not be long. But it took him forever. I realized that I was alone. I could not come out of the house, so I opened the window. I was so desperate. So lonely. So betrayed. At that moment I pulled the curtain so strongly that I fell on the floor. And there I was standing-one little criminal-desperate to escape and knowing that I would be punished for destroying the curtain that was not even ours.
But then something changed. I stopped weeping. I looked around and realized that I was in a safe place, and that mom would come back and kiss me no matter what I had done.
This was a moment of pure happiness, not the happiness of getting a new toy or a dog, or going to the party of your best friend. It was the moment of clarity for me-the first time in my life when I realized that I was happy to have my mom and that I was safe. My eyes saw the world in different shades that moment. And by the way-I was not punished for the curtain. I fell asleep on my mom's knees.
1.What is the best title for this passage?
A. An Unforgettable Party
B. A Childhood Memory
C. A Happy Day in My Mom's Best Friend's Home
D. The Rules You Should Follow
2.What best describes the author's feelings toward childhood memories?
A. Childhood memories are easy to forget.
B. They make what is the personality of a man.
C. Good memories are always much easier for us to remember.
D. Childhood memories are always strange and incomprehensible.
3.What happened to the author when he was 6 years old?
A. His family moved to another apartment.
B. He always fought with mom's friend's children for toys.
C. He was punished by his mom for destroying her friend's curtain.
D. He was locked inside a house and failed to get out by the window.
4.In the last paragraph, the word " It " refers to______.
A. the moment he received a present from his mom
B. the time he spent in mom's friend's home
C. the moment he realized his mom's love
D. the time he destroyed the curtain
Whistler World ski Snowboard Festival
There are many reasons why the World Ski& Snowboard Festival has been so popular for the past 22 years. Known to locals as WSSF, the festival combines spring energy with Whistlers unique mountain culture. It is being held from 10th April to 15th April, at the Whistler Conference Centre in Whistler. Canada. There are photography, filmmaking, ski and snowboard competitions.
WSSF Schedule
Below are some of the events.
Tuesday, April 10
Eight famous adventurers give visual stories to the audience. The eight people include mountain bikers Darren Berrecloth and Hans Rey, climber John Long, diver Jill Heinerth, snow boarder Alex Warburton, skier Johnny Thrash, and adventurers Casey Brown and Ted Baird.
Wednesday, April 11
This free exhibit gives you a deeper look at mountain culture. It goes further than simply landscapes and wildlife. The exhibit will be open to everyone from April 1l to April 13.
Teams have 72 hours to shoot, edit and produce a short film taken within 100 kilometres of Whistler Village. Judges will choose just one winner for“ Best of show”.
Thursday, April 12
Six photographers compete to amaze the judges and the audience with pictures that record sports, culture and the human spirit.
Friday, April 13
Whistler Blackcomb is the fourth stop in British Columbia, Canada, for this snowboard contest. The contest is free to enter and the two champions (man and woman) will share C $50, 000.
Saturday, April 14
Competitors include a mix of racing legends. The audience can view the ski race for free. * The ski race depends on the weather and is scheduled for Saturday, April 14 but may be moved to Friday, April 13-check wssf. com for up-to-date information.
1.What can we learn about the World Ski Snowboard Festival?
A. It is a seven-day festival
B. It is held in April every year.
C. It has a history of over twenty years.
D. It is best known for whistlers mountain culture.
2.What can visitors do during the World Ski Snowboard Festival?
A. Enjoy films made by competitors on April 11.
B. See eight famous mountain bikers on April 10.
C. Watch a ski race that will definitely happen on Saturday.
D. View an exhibit featuring mountain culture on April 12.
3.Which of the events mentioned in the text offers a prize?
A. The ski race.
B. The snowboard contest.
C. The photography competition.
D. The filmmaking competition.
疫情期间，学校都延期开学，老师通过建立QQ学习群来组织教学和管理。假如你是李华，你的美国朋友Jack来信询问QQ学习群对居家学习是否真的有帮助，请你回复。
回信内容包括：
1. QQ学习群的利
2. QQ学习群的弊
3. 你的观点
参考词汇：新型冠状病毒肺炎：COVID-19；：QQ学习群：QQ study group
注意事项：1. 词数100左右；
2.注意回信的开头和结尾，可以适当增加细节，以使行文连贯。
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文中共有10处语言错误，每句中最多有两处。每处错误仅涉及一个单词的增加、删除或修改。
增加：在缺词处加一个漏字符号（∧），并在其下面写出该加的词。
删除：把多余的词用斜线（﹨）划掉。
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2、只允许修改10处，多者（从第11处起）不计分。
The day before yesterday, I went to the bookstore where is near my school to buy a reference book. It was Saturday, so there was many people. Under the help of the shop assistants, I quickly got the book I needed. I was about to leave while I found someone trying to steal a man's money. Although I was nervous, but I tried to think of a way to help. Suddenly, a good idea occurred me. I stepped on the man's foot by purpose. As was expected, the man's scream gives the thief a fright, who quickly walked out of the shop. After hear my explanation, the man smiled and showed great gratitude to him.
