So far scientists have done a lot of research...

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

（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

_____ people have done lots of research on moon, there is still much waiting to be discovered.

A. If　　 B. Since　　 C. Because　　 D. Though

九年级英语单选题中等难度题查看答案及解析

_____ people have done lots of research on moon, there is still much waiting to be discovered.

A.If B.Since C.Because D.Though

九年级英语单选题中等难度题查看答案及解析

Lots of scientists are working hard _____ send astronauts to Mars.

A. so　　 B. but

C. in order to　　 D. so that

九年级英语单选题中等难度题查看答案及解析

Lots of scientists are working hard 　　 send astronauts to Mars one day.

A. so that　　 B. in order　　 C. in order to　　 D. and

九年级英语单选题中等难度题查看答案及解析

The universe is really mystical(神秘的). Scientists have done lots of study about it but there is still much they haven’t discovered. ___ think that people have lived on the earth for many many years. However, we haven’t found life on any other planets _____.

There _____ eight planets going around the sun. The earth is one of them. There are humans, animals, plants and many other kinds of _____ on the earth. There is water and air, too. And compared to the other planets, the earth is not too _____ or too cold. None of seven other planets has a(n) _____ like that of the earth.

The sun and its planets are_____the solar system, and our solar system is a small part of a much larger group of stars and planets, called the Galaxy or the Milky Way. There are billions of_____ in the Galaxy, and our sun is only one of them.

Scientists have also_____many other galaxies in the universe. Their light has to travel for many years to reach us. So how______ is the universe? It is impossible to imagine______.

Scientists have sent spaceships to the planet Mars to take______photos. They have______ sent spaceships to travel outside the solar system. However, no spaceship has travelled far enough to reach other stars in _____ Galaxy.

When we see stars twinkling(闪耀) in the sky at night, we may think a lot:with so many stars in the universe, is there life out there in space? If there is life on other planets, what life will be like there? What transports do they use to travel______? Why don’t they visit us? We do not know the answers...

1.A. Workers　　 B. Doctors　　 C. Scientists　　 D. Managers

2.A. yet　　 B. already　　 C. still　　 D. just

3.A. is　　 B. are　　 C. was　　 D. were

4.A. plant　　 B. life　　 C. animal　　 D. nature

5.A. cool　　 B. warm　　 C. hot　　 D. wet

6.A. lesson　　 B. house　　 C. expression　　 D. environment

7.A. caused　　 B. carried　　 C. explained　　 D. called

8.A. lights　　 B. rivers　　 C. stars　　 D. gods

9.A. discovered　　 B. invented　　 C. produced　　 D. prevented

10.A. large　　 B. far　　 C. wide　　 D. long

11.A. introduce　　 B. overcome　　 C. appear　　 D. imagine

12.A. fetch　　 B. take　　 C. carry　　 D. bring

13.A. pretty　　 B. just　　 C. even　　 D. also

14.A. her　　 B. our　　 C. its　　 D. his

15.A. travel　　 B. serve　　 C. throw　　 D. beat

九年级英语完型填空中等难度题查看答案及解析

根据句意，写出括号内所给单词的适当形式。

1.We all know there are lots of ______ (advantage) of living on Mars, so we won’t move out of Earth to Mars.

2.______ (hope), we can finish the project before this weekend.

3.Do you think it’s good for them to keep worries which were caused by others to _____ (they), guys?

4.The ______ (strict) the parents are, the more stressed their children will become.

九年级英语单词拼写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

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