Did you hear of the supercomputer? Recently, China’s Tianhe-1 (天河一号) was ranked as the world’s fastest supercomputer, according to a new list of world’s TOP 500 supercomputers.
It took 200 Chinese scientists two years to build the fastest supercomputer. It can do 2,507 trillion (万亿次) calculations in a second! That means it will take a personal computer 600 years to finish the work that a supercomputer does in a day!
The US now leads the world in the area of supercomputers. It is home to more than half of the world’s top 500 supercomputers. Japan also has advanced technology. China is developing its supercomputer technology quickly. But experts say it will take years before China’s total computing power can catch up with that of the US.
Supercomputers can work on many different things. They can solve problems in areas like national defense (国防), energy and science. In business, you can also use supercomputers. Oil companies use them to find oil and gas. Banks use them for quick trades. Food companies even use supercomputers to make sure that they put potato chips into cans without breaking them.
To make a supercomputer, scientists first need to link (连接) thousands of small computers together. Then they use software to turn them into one supercomputer. In fact, any person with enough knowledge about computers can make a supercomputer. But you need the top technology to make a supercomputer run fast.The world’s fastest supercomputer ________.
| A．was made in America |
| B．was made within two months |
| C．can do 2,507 trillion calculations in a minute |
| D．was made by 200 Chinese scientists |
Among the world’s top 500 supercomputers, ________ of them are made in the US.
| A．less than 20% | B．more than 50% |
| C．less than 50% | D．more than 20% |
The main idea of the fourth paragraph is ________.
| A．supercomputers can be used in different kinds of areas |
| B．supercomputers can work fast |
| C．supercomputers can only be used to find oil and gas |
| D．supercomputers can be used to make money |
According to the passage, to make a supercomputer, ________.
| A．you needn’t know enough knowledge about computers |
| B．you need to know how to play computer games |
| C．scientists first need to link thousands of small computers together |
| D．scientists first need to make some software |
Which of the following is true?
| A．A personal computer needs 300 years to finish the work that a supercomputer does in a day. |
| B．Japan now leads the world in the area of supercomputers. |
| C．Supercomputer can be used by food companies. |
| D．Scientists needn’t use software to turn small companies into one supercomputer. |
Many objects in the universe are invisible ，but they send radio waves．The radio telescope *thus appeared，and it is considered one of the greatest inventions in the twentieth century．Reber built the world's first radio telescope in 1937．Ryle and Hewish developed radio telescope systems for the location of weak radio sources，and they shared the Nobel Prize for Physics in 1974．
A radio telescope is usually made up of：
•One or more antennas to collect the radio waves．Most antennas are made in the shape of a dish to collect and reflect *the radio waves to the sub﹣reflector，in the same way as a curved mirror focuses visible light to one point．
•A receiver and amplifier to receive the radio waves from the sub﹣reflector，and make these weak radio waves strong enough to be recorded and turned into electronic signals *．To make an amplifier sensitive enough，it is usually cooled to very low temperatures（e．g．as low as ﹣270℃）．
•A recorder to keep a record of the electronic signals．Most radio telescopes today keep the signals to the computer's memory disk for astronomers to analyze later．
Radio wavelengths are much longer than those of visible light．and the radio waves from deep space are always weak．To catch these waves，radio telescopes usually have huge antennas．The sizes of most antennas in use today are around 50 to 300 metres in diameter． The antenna of FAST in Guizhou，China，the latest and largest radio telescope in the world，is 500 metres in diameter，as large as the size of 30 football fields．
To avoid interferences， and keep the telescopes sensitive，radio telescopes are built in places where there are no human radio waves or electronic signals．For example，FAST is 5 kilometres away from the closest village and 25 kilometres away from the nearest town．
Radio telescopes create pictures of the sky，not in visible light， but in radio waves．This is extremely useful，because there are objects that can't be seen，objects that we wouldn't even know were there without radio telescopes．
（1）Radio telescopes help collect from the universe．
A．light
B．objects
C．radio waves
D．visible signals
（2）Most antennas of radio telescopes are made in the shape of a dish to ．
A．make the antennas strong enough
B．increase the number of radio waves
C．turn radio waves into electronic signals
D．focus radio waves on the sub﹣reflector
（3）The underlined word "interferences" in the passage refers to ．
A．the noises made by villagers and animals
B．the sounds from the radios and televisions
C．the people who go to Guizhou to watch FAST work
D．the radio waves and electronic signals from humans
（4）What have we done with the help of radio telescopes？
A．We have received pictures of deep space．
B．We have discovered unknown lives in the universe．
C．We have found some unknown objects in the universe．
D．We have turned the radio waves from space into light．
Have you ever jumped on a trampoline？ Today many people use it for exercise．
Back in the 1980s，researchers found that jumping on a trampoline was a good way to help astronauts regain their strength．Actually，trampolining has many advantages．It helps bones*and muscles*grow and improves your balance by stimulating *the inner ear．It is especially useful for increasing flow of the lymphatic system，which helps your body get rid of harmful toxins．Trampolining has benefits similar to those of running，but without too much stress on knees and ankles．
If you would like to start trampolining，you may first need to ask a doctor to make sure it's a safe activity for you．It's easy to find an inexpensive trampoline， but it should be well﹣made and strong enough to support your weight．To avoid accidents，some trampolines have a safety net around them．Remember： whenever you are on a trampoline，be careful not to jump near the edge of it．
Here are a few exercises for beginners；
•High Knee Lift．Raise one knee at a time．Lift your knee higher than you usually do when you are running．
•Star Jump．Jump into the air and spread your arms and legs into a star shape．As you gain more confidence，practice more difficult levels：
•Tuck Jump．At the top of your jump， bring the knees to the chest*，with the arms holding the legs．
•Pike Jump．Jump high，bring the legs up，and point the toes *forward．Touch your toes with hands．
There are many more exercises you can try．Happy trampolining!
（1）According to the passage，what benefit can we get from trampolining？
A．It helps with bone growth．
B．It cures illnesses in our knees．
C．It helps reduce stress on muscles．
D．It prevents ears from being hurt．
（2）How can we do trampolining safely？
A．Buy an expensive trampoline．
B．Jump in the center of a trampoline．
C．Choose a trampoline without a net．
D．Lose weight before starting trampolining．
（3）Which picture shows Tuck Jump？
（4）This passage introduces ．
A．an exercise to improve our fitness
B．an exercise to gain self﹣confidence
C．a way to keep balance when we jump
D．a way to avoid accidents when exercising
Hot Dog is popular． It's not a dog， but a cooked sausage in a long piece of bread． Here are some stories and facts about it from English websites．
|
HISTORY of Hot Dog |
|
HOT DOG FUN FACTS |
The 1600s A German called Johann Georghehner created the"dachshund"sausage．"Dachshund"is a German small long thin dog． The 1860s The very first hot dog ﹣the"dachshund"sausage in a roll﹣was sold by Germans in New York．It became popular in the US later． 1871 Charles Feltman，a German，started the first Coney Island hot dog stand．It made hot dogs known to more people． 1893 Chris Von Der Ahe started the American tradition of eating hot dogs at baseball parks，making hot dogs more popular． 1901 A New York cartoonist，Tad Dorgan，saw the red hot "dachshund" sausages sold on streets．He wanted draw picture of it，but he wasn't sure how to spell "dachshund"， so he simply wrote" Hot Dog"． It is widely believed how Hot Dog had its name． 1949 The first vegetarian hot dogs came out． |
World record for eating hot dogs：73 in ten minutes |
|
|
|
Hot dogs were one of the first foods eaten on the moon! |
||
About 150 million hot dogs are eaten by Americans each July 4th． |
|
||
|
About 21 million hot dogs were sold at American baseball parks in 2010． |
||
New Yorkers eat more hot dogs than any other city population in the US． |
|||
（1）Americans started the tradition of eating hot dogs at baseball parks in ．
A．1871
B．1893
C．1901
D．1949
（2）It's believed that the name"Hot Dog "was created by ．
A．Tad Dorgan
B．Charles Feltman
C．Chris Von Der Ahe
D． Johann Georghehner
（3）What can we know about hot dogs from the passage？
A．New Yorkers like eating hot dogs most in the world．
B．Germans eat about 150 million hot dogs each July 4th．
C．A world record says someone ate 73 hot dogs in 10 minutes．
D．About 21 million hot dogs were sold in America in the 1860s．
Tourism （旅游业）is one of the world's largest industries． Many countries depend heavily on tourism as an important part of their economy（经济）， while other countries﹣such as some of the smaller Caribbean island nations﹣are almost completely dependent on tourism．
Despite its economic advantages，tourism has disadvantages， too． While countries spend millions attracting tourists， they are also under the pressure that tourism brings．
One of the biggest problems is environmental． The building of roads and hotels can quickly destroy those very beautiful places． Development on wetlands，for example， influences wildlife； forests disappear as they are cleared to make way for buildings and to provide fuel （燃料）． In addition， the tourist industry also puts a huge pressure on water people need． In dry Mediterranean areas， tourists use almost twice as much water as local people when swimming in the pool．
Tourism is also responsible for producing plenty of waste． Cruise ships in the Caribbean produce a lot of rubbish﹣more than 70，000 tons each year． It even has an influence on places far away like the Himalays，the word's highest mountain， which has more than 100 tons of rubbish sitting on it．
In spite of those problems， tourism can be good for communities and the environment． The park﹣entrance fees（费用）are paid for the protection of places of interest or the animals． What's more， tourism brings people closer to nature， and can give them a better understanding of the environment and the result of destroying it．This leads to pressure on local governments to protect these beautiful areas，and can result in the protection of endangered plants and animals． Also， it can provide people with more opportunities to find jobs in the tourist industry．
Although tourism has many advantages， it clearly has a bad influence as well． The challenge for local and national governments is to manage tourism so that communities can benefit economically， and yet at the same time， make sure that the tourist areas are kept for all to enjoy．
（1）Paragraph 3 and Paragraph 4 mainly talk about the of tourism．
A．disadvantages
B．development
C．importance
D．survey
（2）The writer shows the waste problem is serious by ．
A．telling stories
B．listing facts
C．asking questions
D．making comparisons
（3）According to Paragraph 5，which of the following are the advantages of tourism？
①The money from tourism is used to protect the environment．
②Tourism can help people better understand the local culture．
③People can get more chances to find jobs related to tourism．
④Humans and nature are becoming closer with the help of tourism．
A．①②③
B．①②④
C．①③④
D．②③④
（4）The writer advises the government to at the end of the passage．
A．attract more tourists
B．care about the economy
C．develop the tourist industry
D．manage tourism well
Brooke wanted a dollhouse and some sugar cookies． So the 6﹣year﹣old asked Alexa to get them． Alexa wasn't her mom or babysitter． It was a voice﹣activated home assistant powered by AI（人工智能）．And it made Brooke's wishes come true． A few days later， much to her parents' surprise， a﹩170 dollhouse and four pounds of cookies showed up． They ate the cookies and gave away the dollhouse to a local hospital．And that's not the end of the story． When a news reporter told the story of what happened on TV， Alexa devices（设备）in many listeners' homes woke up and tried to order dollhouses!
Alexa isn't the only AI willing to serve you． Apple HomePod has Siri， Google Home has its Assistant， and the upcoming Galaxy Home device will have Bixby． People who
have these devices use them mainly for listening to music， checking the weather， and setting timers． According to a report from The Information， nowadays voice shopping is rare． But many scientists predict
a boom（增长）in voice shopping in the near future． Is that a good thing？
▲． You can shout out an order as soon as you think of it， even if you are cooking，cleaning， or driving． In addition， people with disabilities who are unable to use a keyboard or mouse can shop without any help．
But voice shopping has its disadvantages． Unwanted dollhouses aren't the biggest problem． It's usually very easy to cancel an order or return products． The thing that worries some people is that these assistants are always listening． They have to be able to respond when you want them． So they listen for "Alexa" or "OK Google" or another order． When they hear it， they start recording the conversation． Some have worried about what happens shopping habits？ And what if someone hacks（入侵） the device？ The CIA found a way to hack smart TVs to turn them into spies that listen all the time． Others could do the same with any smart device．
What do you think？ Are you ready to start voice shopping？
（1）From the passage， we know that Alexa ．
A．can look after the baby
B．can cook delicious food
C．is a toy doll sold online
D．is one kind of AI device
（2）The underlined word "rare" in Paragraph 2 probably means ．
A．unusual
B．expensive
C．harmful
D．impossible
（3）Which of the following is the best to fill in the "▲" in Paragraph 3？
A．Convenience is the main advantage of voice shopping
B．The cost of voice shopping is lower than other ways
C．The popularity of voice shopping is increasing
D．The technology of voice shopping needs improving
（4）Paragraph 4 mainly tells us that B when people try voice shopping．
A．AI sometimes forgets people's orders
B．personal information might be hacked
C．It's difficult to cancel or return products
D．the needs for products can't be satisfied
粤公网安备 44130202000953号