There’s no pizza on Mars, but scientists have found a solution to this problem for hungry astronauts: a pizza printer! NASA, the American space agency, has developed a machine that “prints” food. They showed a model of the printer in Austin, Texas last month.
How does it work? Cartridges(墨盒) filled with powdered dough(面粉团), cheese, sauce, water and oil put the ingredients layer(层)by layer onto a printer bed. The printer bed, which gets hot from below, cooks the food as it’s being printed.
Since most of the ingredients are powdered, they can be sent into space and stored for many years without going bad. Water makes food go sour, so the food powders are mixed with water and oil only when they are being printed.
“Long-distance space travel requires more than 15 years of shelf life for food.” says Anjan Contractor, whose company developing the printer. “ We take water out, and in that form, food will last maybe 30 years.”
In outer space, there are far fewer choices for astronauts for dinner. Most of their foods—even things like beef or shrimp—are eaten from bags as powders（粉末）. Scientists hope the new food printer can be used to make more delicious food in outer space, keeping astronauts healthier and happier.
But the printer is not limited to use in outer space. Scientists think it could be useful on Earth, too. It could allow personal meals to be made at the dinner table, according to each person’s different needs.
“Let’s say someone is an athlete in the family, and he needs more protein(蛋白质),” says Anjan Contractor, founder of Systems and Materials Research Corp, the company developing the printer. “We can design recipes for him and print out more protein-nutritious food for him.”
1.In outer space, food can be stored for many years without going bad____.
A. when it’s mixed with water
B. when it’s mixed with oil
C. when it’s powdered
D. when it’s put in the fridge
2.Which of the following is TRUE? ______
A. Astronauts eat beef powder in outer space.
B. A model of the food printer was shown in New York last month.
C. Only astronauts and athletes can eat the food from the printer.
D. The printer can only be used in outer space.
3.What is the best title for this passage? _______
A. Astronauts’ Life in Outer Space
B. Hungry? Just Print!
C. How to Make Pizza
D. Long Lasting Food
九年级英语阅读理解中等难度题
There’s no pizza on Mars, but scientists have found a solution to this problem for hungry astronauts: a pizza printer! NASA, the American space agency, has developed a machine that “prints” food. They showed a model of the printer in Austin, Texas last month.
How does it work? Cartridges(墨盒) filled with powdered dough(面粉团), cheese, sauce, water and oil put the ingredients layer(层)by layer onto a printer bed. The printer bed, which gets hot from below, cooks the food as it’s being printed.
Since most of the ingredients are powdered, they can be sent into space and stored for many years without going bad. Water makes food go sour, so the food powders are mixed with water and oil only when they are being printed.
“Long-distance space travel requires more than 15 years of shelf life for food.” says Anjan Contractor, whose company developing the printer. “ We take water out, and in that form, food will last maybe 30 years.”
In outer space, there are far fewer choices for astronauts for dinner. Most of their foods—even things like beef or shrimp—are eaten from bags as powders（粉末）. Scientists hope the new food printer can be used to make more delicious food in outer space, keeping astronauts healthier and happier.
But the printer is not limited to use in outer space. Scientists think it could be useful on Earth, too. It could allow personal meals to be made at the dinner table, according to each person’s different needs.
“Let’s say someone is an athlete in the family, and he needs more protein(蛋白质),” says Anjan Contractor, founder of Systems and Materials Research Corp, the company developing the printer. “We can design recipes for him and print out more protein-nutritious food for him.”
1.In outer space, food can be stored for many years without going bad_______.
A．when it’s mixed with water
B．when it’s mixed with oil
C．when it’s powdered
D．when it’s put in the fridge
2.Which of the following is TRUE? ______
A．Astronauts eat beef powder in outer space.
B．A model of the food printer was shown in New York last month.
C．Only astronauts and athletes can eat the food from the printer.
D．The printer can only be used in outer space.
3.What is the best title for this passage? _______
A．Astronauts’ Life in Outer Space
B．Hungry? Just Print!
C．How to Make Pizza
D．Long Lasting Food
九年级英语阅读理解中等难度题查看答案及解析
There’s no pizza on Mars, but scientists have found a solution to this problem for hungry astronauts: a pizza printer! NASA, the American space agency, has developed a machine that “prints” food. They showed a model of the printer in Austin, Texas last month.
How does it work? Cartridges(墨盒) filled with powdered dough(面粉团), cheese, sauce, water and oil put the ingredients layer(层)by layer onto a printer bed. The printer bed, which gets hot from below, cooks the food as it’s being printed.
Since most of the ingredients are powdered, they can be sent into space and stored for many years without going bad. Water makes food go sour, so the food powders are mixed with water and oil only when they are being printed.
“Long-distance space travel requires more than 15 years of shelf life for food.” says Anjan Contractor, whose company developing the printer. “ We take water out, and in that form, food will last maybe 30 years.”
In outer space, there are far fewer choices for astronauts for dinner. Most of their foods—even things like beef or shrimp—are eaten from bags as powders（粉末）. Scientists hope the new food printer can be used to make more delicious food in outer space, keeping astronauts healthier and happier.
But the printer is not limited to use in outer space. Scientists think it could be useful on Earth, too. It could allow personal meals to be made at the dinner table, according to each person’s different needs.
“Let’s say someone is an athlete in the family, and he needs more protein(蛋白质),” says Anjan Contractor, founder of Systems and Materials Research Corp, the company developing the printer. “We can design recipes for him and print out more protein-nutritious food for him.”
1.In outer space, food can be stored for many years without going bad____.
A. when it’s mixed with water
B. when it’s mixed with oil
C. when it’s powdered
D. when it’s put in the fridge
2.Which of the following is TRUE? ______
A. Astronauts eat beef powder in outer space.
B. A model of the food printer was shown in New York last month.
C. Only astronauts and athletes can eat the food from the printer.
D. The printer can only be used in outer space.
3.What is the best title for this passage? _______
A. Astronauts’ Life in Outer Space
B. Hungry? Just Print!
C. How to Make Pizza
D. Long Lasting Food
九年级英语阅读理解中等难度题查看答案及解析
—Have scientists found life on Mars?
—Not yet, but I think they ________it some day.
A.find B.found C.have found D.will find
九年级英语单选题中等难度题查看答案及解析
（2017·浙江温州· 6）________ the scientists have done lots of research on Mars，there is still much waiting to be discovered.
A. If B. Since C. Unless D. Though
九年级英语单选题中等难度题查看答案及解析
There’s no fruit ____ vegetables on Mars.
A. and B. but C. or D. except
九年级英语单选题中等难度题查看答案及解析
Is there intelligent life on other planets? For years， scientists said “no” or “We don’t know.” But today this is changing. Seth Shostak and Alexandra Barnett are astronomers. They believe intelligent life exists (存在) somewhere in the universe. They also think we will soon contact these beings.
Why do Shostak and Barnett think intelligent life exists on other planets? The first reason is time. Scientists believe the universe is about 12 billion years old. “This is long enough for other planets to have intelligent life，” say Shostak and Barnet. The second reason is size—the universe is huge. “Tools like the Hubble telescope（哈勃望远镜）have shown that there are at least 100 billion galaxies，” says Shostak. “And our galaxy， the Milk Way， has at least 100 billion stars. Some planets going around these stars might be similar to Earth.”
In the past， it was hard to look for signs of intelligent life in the universe. But now， powerful telescopes(高倍望远镜) allow scientists to discover smaller planets—the size of Mars or Earth in other solar systems. These planets might have intelligent life.
Have beings from space already visited Earth? “Probably not，” says Shostak. “It’s a long way away. However， intelligent beings may contact us in other way， such as radio signs. In fact， they may be trying to communicate with us now， but we don’t have the right tools to receive their messages. However， this is changing. By 2025， we could make contact with other life forms in our universe and we might help each other.”
1.Seth Shostak and Alexandra Barnett are _______________.
A. astronomers. B. farmers C. singers D. drivers
2.What is the best title for Paragraph Two?
A. The Age and Size of Earth
B. Our Galaxy： The Milk Way
C. Why Intelligent Life Might Exist
D. Earth： The Only Planet With Intelligent Life
3.Why was it hard to look for signs of intelligent life in the universe in the past?
A. There were not any smaller planets.
B. There were not any powerful telescopes.
C. The astronomers were not interested in them.
D. The Milk Way didn’t exist at that time.
4.Why haven’t beings from space visited us yet according to Shostak?
A. They are afraid of us.
B. It’s a long way away.
C. They don’t want to see us.
D. They don’t know how to use radio signs.
5.What does the underlined phrase “life forms” in the last paragraph mean?
A. Messages. B. Tools.
C. Intelligent beings. D. Radio signs.
九年级英语阅读理解中等难度题查看答案及解析
Is there intelligent life on other planets? For years，scientists said "no" or "We don't know". But today this is changing. Seth Shostak and Alexandra Barnett are astronomers. They believe intelligent life exists(存在)somewhere in the universe. They also think we will soon contact these beings.
Why do Shostak and Barnett think intelligent life exists on other planets? The first reason is time. Scientists believe the universe is about 12 billion years old. "This is long enough for other planets to have intelligent life，" say Shostak and Barnett. The second reason is size-the universe is huge. "Tools like the Hubble telescope(哈勃望远镜)have shown that there are at least 100 billion galaxies，" says Shostak. "And our galaxy，the Milk Way，has at least 100 billion stars. Some planets going around these stars might be similar to Earth."
In the past，it was hard to look for signs of intelligent life in the universe. But now，powerful telescopes(高倍望远镜)allow scientists to discover smaller planets-the size of Mars or Earth in other solar systems. These planets might have intelligent life.
Have beings from space already visited Earth? "Probably not，" says Shostak. "It's a long way away. However, intelligent beings may contact us in other ways，such as radio signs. In fact，they may be trying to communicate with us now，but we don't have the right tools to receive their messages. However, this is changing. By 2025，we could make contact with other life forms in our universe and we might help each other. "
1.What is the best title for Paragraph Two?
A. The Age and Size of Earth
B. Our Galaxy: The Milk Way
C. Why Intelligent Life Might Exist
D. Earth: The Only Planet With Intelligent Life
2.Why was it hard to look for signs of intelligent life in the universe in the past?
A. There were not any smaller planets.
B. There were not any powerful telescopes.
C. The astronomers were not interested in them.
D. The Milk Way didn't exist at that time.
3.Why haven't beings from space visited us yet according to Shostak?
A. They are afraid of us.
B. It's a long way away.
C. They don't want to see us.
D. They don't know how to use radio signs.
4.What does the underlined phrase "life forms" in the last paragraph mean?
A. Messages. B. Tools.
C. Intelligent beings. D. Radio signs.
九年级英语阅读理解中等难度题查看答案及解析
So far scientists have done a lot of research on Mars successfully.（改为被动语态）
So far a lot of research on Mars ________ ________ done successfully by scientists.
九年级英语改写句子困难题查看答案及解析
We have found plastic in the ocean and in animals. But for the first time, scientists have found plastic in human poop（粪便）,USA Today reported.
The findings came from a study by scientists from Environment Agency Austria. The researchers followed eight healthy volunteers from different parts of the world. The volunteers wrote down what they ate for a week and then provided a stool sample（大便样本）for testing.
Scientists found nine different types of plastic particles（ 颗粒）in the samples. “The smallest plastic particles are able to enter the bloodstream, the lymphatic system （淋巴系统）,and may even reach the liver（肝脏）”said Philipp Schwabl, who took part in the research.
However, the scientists aren't sure if this plastic is harmful to humans. They're not sure how the plastic got into the volunteers' bodies, either. But most of the volunteers said they drank from plastic bottles and also ate seafood that could include plastic from ocean pollution.
In fact, plastic is everywhere around us. Every year, about 8 million tons of plastic waste goes into the oceans. There, sunlight and waves break the plastic down to small particles. Most of the particles stay in the ocean. Others can spread into the soil and air. Could plastic in the air fall onto food and get into the human body?
According to USA Today, 90 percent of sea salt sold in the world includes plastic. And even some top water has been found to have plastic particles in it.
1.According to USA Today, what have scientists found for the first time?
A.Plastic in the ocean. B.Plastic in animals.
C.Plastic in human poop. D.Plastic in the soil.
2.The researchers________according to the second paragraph.
A.followed eight healthy volunteers. B.are from Environment Agency Australia
C.wrote down what they ate for a week D.provided a stool sample for testing
3.Paragraph 3 is written to tell us that________
A.plastic particles can be a few different sizes B.plastic particles can reach many parts of our bodies
C.plastic can harm the lymphatic system D.plastic particles are inside all of us
4.What can we infer （推断） from the study?
A.Plastic does no harm to our bodies.
B.The best way to deal with plastic waste is to burn it.
C.People should stop drinking tap（水龙头）water.
D.It can be hard to avoid plastic in food and drinks.
九年级英语阅读单选中等难度题查看答案及解析
For centuries, humans have wondered whether there is life on Mars. Why is Mars losing its air? Last week, the question was answered.
“The answer, is blowing in the wind,” said Michael Meyer. He is the lead scientist for Mars Exploration Program.
It turns out solar winds from the sun are slowly stripping( 除掉) away Mars' air. That is what scientists explained at a press conference.
Bruce Jakosky is the principal investigator on the MAVEN team. It is a spacecraft that collects information from Mars as it circles around the planet.
Today, Mars has a thin atmosphere. It is cold and dry. ______
"When we look at ancient Mars, we see a different type of surface. One that had valleys that looked like they were carved by water, lakes that were standing for a long period of time. We see an environment that was much more able to support liquid water."
Recently scientists found a kind of liquid water that flows with salt down a mountain area of the planet. But, it is not always there. Scientists already knew that ice exists on Mars. So why is it important to find liquid water?
"It means that we have a resource. And when we're looking at sending humans to Mars, water is one of the key things that we need to have. Not only for the astronauts to drink, but also to make oxygen and fuel."
Sending humans to Mars will be in the 2030s. Those chosen might fly any number of space vehicles still in development.
Human beings are developing rockets and spacecraft to get people to Mars. Scientists want to know how the human body reacts to being in space for long period of time.
Whether there is life on Mars remains unanswered. But some scientists think there might be some kind of microbial life on the planet. Finding life on another planet would change the way we view the whole universe.
1.What was the surface of ancient Mars like?
A. It had thin air. B. It was dry.
C. It had valleys that looked like they were carved by water. D. It had no water.
2.Which statement is TRUE according to the passage?
A. The surface of the Mars is different from it used to be.
B. Scientists have known whether there is life on Mars.
C. People can not send humans to Mars forever.
D. There is not any atmosphere on Mars.
3.What does the underlined word "Those" in the text refer to?
A. Scientists B. Rockets C. Astronauts D. Vehicles
4.Which of the following is the best for“______”in Paragraph 5?
A. But it used to be much different. B. It was the same case in the past.
C. It's always like this. D. It will be different in the future.
九年级英语阅读单选中等难度题查看答案及解析