Researchers have used very small electronic devices to make jllfish (水母) stronger and faster. The scientists say they used these electronic jelly fish in the hopes of sending them to study and explore the world's seas.
A report on the experiment was published in the magazine Science Advances. The study shows jllyfish are unusual living things. They move through seawater by reducing the size of their muscles. For the experiment, the researchers put an electronic device, about 2 centimeters in length, inside a moon jelly fish, a common kind of jelly fish.
The researchers said the device caused jellyfish to move their bodies more often. They swam around three times faster than usual. Jelly fish are known to produce something from time to time when they are feeling stressed. No such action appeared during the study. "Care is taken to the jellyfish, " Dabiri explained. "The jellyfish swam the same when the electronic device was taken away after the experiment, " the researchers said
"It's very unusual and modern. It seems to happen only in the future. " said Xu, an engineer at Stanford University. "We could send these jellyfish to different areas of the sea to get signs of climate change or have a close watch on nature. "“One of the first purposes will be going deep, " added Dabiri. "Going deep is important because humans need to understand the deep seas.”
"Generally, we'd put these jllyfish at the surface, have them sw im down to increasing depths, and make them back to the surface with data. Before that the electronic devices help us see just how far we can get them to go down into the sea," Xu said.
"Jelly fish have lived on earth for over 500 million years, and over that time, their bodies have nearly remained unchanged," said Xu. "So it's interesting to find out what makes them so special in the sca and how we can learm from them. " Xu added, "We use animals with natural sw imming abilitics instcad of submarines ( 潜水艇) which might harm the env ironment. "
11. What happened to a jelly fish during the experiment?
A. It reduced its muscle size and swam faster.
B. It swam around four times faster than usual.
C. It felt stressed and sometimes produced things.
D. It swam more slowly with the electronic device.
12. The purpose of the experiment is to
A. get natural signs and study the sea surface
B. make the jellyfish much stronger and faster
C. study the deep sea and learm more about nature
D. go deep into the sea and find other living things
13. Which of the following is the correct order of the experiment?
A. Make the jellyfish back w ith data.
B. Put the jellyfish at the surface.
C. Make the jellyfish swim down.
D. Put electronic devices on jellyfish.
D. d-a-b-c .
14. Scientists used jllyfish in the experiment because jllyfish
A. are special and not bad for environment
B. have already lived on carth for a long time
C. help us protect env ironment like submarines
D. can move faster and become larger in the sca
15. What is the passage mainly about?
A. Researchers find new ways to protect nature.
B. Jellyfish become faster with electronic devices.
C. Scientists use jllfish to explore the deep seas.
D. Jllyfish are important in protecting enviropment.
II. Vocabulary and Structure (本题共25小题，每题1分，共25分)
Directions: For each of the follow ing sentences there are four choices marked A, B, C and D. Choose the one answer that best completes the sentence.
16.- There is X-ray machine in the hall.
-Well, it is used to check if people take dangerous things with them.
A.a B. an C. the D. one
17. The scarf silk soft and comfortable.
A. made from; feel
B. made of, feels
C. is made of; feels
D. made up of; feel
18. Hainan is famous its beautiful beaches. It is famous an interational island.
A. for; as
B. as; for
C. as; as
D. for; for
19.一Do you mind my the window?
It is really cold outside.
A. close; No, not at all
B. closing; Yes, please
C. close; Yes, please
D. closing; No, not at all
20. The virus may destroy and some files in your computers will disappear.
A. mouse B. key board C. programs D. screen
21. will I receive the T-shirt, Madam? In two or three days, boy.
A. How long
B. How soon
C. How many
D. How far
22. I strongly believe that my dream will come true even though many people laugh at me.
A. some day
B. some days
C. every day
D. a day
23. The stories in this film are in that one.
A. same as those
B. different from those
C. similar to that
D. like that
24. Alice some good advice, and she gladly Miss Green's.
A. gave; accepted
B. gave; was received
C. was given; received
D. was given; accepted
25. I think wiser to choose public transport than to drive cars.
A. this B. that C. it D. thatis，
26. Cao Yuan, a young Chinese scientist, has the world with his papers published in Nature, a world-famous science magazine.
A. supposed B. surprised C. suceeded D. suggested
27.- People should still keep a social distance these days
一Yes. A large number of masks in the following months,
B. are needed
C. were needed
D. will be needed
28.- Have you heard that our neighborhood is going to carry out garbage-sorting?
Yes, I can't support it more. it may be hard for us to change our long term habits, it's time for us to do something for a better eny ironment.
A. Though B. Because C. Unless D. If
29. People used to think that wearing masks was only necessary for special groups of people such as medical workers, but now they are coming to realize that it can provide from virus and sickness.