Why are some people better able to beat the flu than others? Part of the answer, according to a new study, is related to the first flu strain we met in childhood.
Scientists from UCLA and the University of Arizona have found that people’s ability to beat the flu virus is decided not only by the sub types of flu they have had throughout their lives, but also by the sequence (顺序) in which they have been infected by those viruses. Their study was published in PLoS Pathogens. The research offers an explanation for why some people become much worse than others when infected with the same strain of the flu virus.
In addition, UCLA scientists, including Professor James Lloyd-Smith, who was also a senior author of the PLoS Pathogens research, recently completed a study that analyzed (分析)travel-related screening(筛查) for the 2019-nCoV. The researchers reported that screening travelers is not very effective for the 2019 coronavirus ― that it will catch less than half of infected travelers, on average ― and that most infected travelers cannot be found out, meaning that they have no symptoms(症状)yet, and are unaware that they have been at high risk. So stopping the spread of the virus is not simply a matter of improving screening methods at airports and other travel centers.
“This puts the responsibility on government officials and public health officials to follow up with travelers after they arrive, to separate them and trace(追踪) their contacts if they get sick later,” said Lloyd-Smith, a UCLA professor of ecology and evolutionary biology(生态学和进化生物学). “Many governments have started to impose quarantines (隔离), or even travel bans, as they realize that screening is not enough to stop the spread of the coronavirus.”
One major concern, Lloyd-Smith said is that other countries, especially developing nations, lack the infrastructure(基础设施)and resources for those measures, and are therefore vulnerable to importing(输入) the disease. “Much of the public health world is very concerned about the virus being introduced into Africa or India, where large populations exist that are not able to receive advanced medical care,” he said.
1.Why is the scientists’ research very important?
A.It explains the cause of the flu virus. B.It reduces the risk of people being infected.
C.It analyzes(分析) people’s ability to fight off the virus. D.It stops the spread of the flu virus all around the world.
2.What do we know about the novel coronavirus from Paragraph 3?
A.Travelers are at high risk of being exposed to it.
B.It is more difficult to stop its spread than expected.
C.Most travelers infected with it are detected by screening.
D.It spreads especially quickly at airports and railway stations.
3.Why does the writer mention Lloyd-Smith’s words in Paragraph 4?
A.To persuade people not to travel. B.To provide a method to kill the virus.
C.To show the harmful effects of the virus. D.To stress(强调) the responsibilities of officials.
4.Which of the following best explains the underlined word “vulnerable” in the last paragraph?
A.Easy. B.Impossible. C.Responsible. D.Indifferent.
How could we tell time if there were no watches or clocks anywhere in the world?
The sun is probably the world’s first “clock”, except in the far north, where the Eskimos(爱斯基摩人)live. There, it’s dark most of the winter, and bright most of the summer. But in most of the world, people have used the sun as a clock. Even today, if you don't have a clock, you can still know that when the sun shines, it’s day and when it’s dark, it’s night. The sun can also tell you if it's morning, noon, or afternoon.
Some people live near the sea. They have their special way to tell time. In the daytime, for about six hours, water rises higher and higher on the beach. And then it goes down and down for about six hours. The same thing happens again at night. There are two high tides and two low tides every 24 hours. Seamen on the ship learn how to tell time by looking at the moon and the stars. The whole sky is their clock.
In some places in the world, the wind comes up at about the same time every day or changes direction or stops blowing. In these places the wind can be the clock.
A sand clock is an even better clock. If you had fine dry sand in a glass, you would have what is called an hourglass. The sand in the hourglass goes from the top part to the bottom in exactly one hour. When the hourglass is turned over, the sand will take another hour to go back again.
1.From the passage we can know there are________ ways to tell time besides the clock and watch.
A.3 B.4 C.5 D.6
2.The Eskimos in the far north can’t use the sun for a clock because________.
A.they know very little about the sun
B.the sun there never goes down in winter
C.it's too cold for them to go out to watch the sun
D.it has long dark winters and long bright summers
3.In which column of a newspaper can you probably read this passage?
A.Entertainment. B.Science. C.Advertisement. D.Sports.
4.What is the best title for the passage?
A.Different Ways to Tell Time B.How the Clock Was Invented
C.The Development of the Clock D.A Useful Machine to Tell Time
One of the main purposes of traveling is to relax and take a break from your normal daily life. Whatever the truth is, we’re not always free to do what we like when traveling to a foreign country, and a US tourist learned that the hard way.
On Aug 12, the unnamed 4l-year-old man was beaten by a passer-by after he was seen giving Nazi salutes(纳粹礼) again and again on a street in Dresden, Germany.
Ever since the end of World War II, Germany has had strict laws to forbid the Nazi salute, as well as other symbols of Nazism.
In fact, most countries have their own taboos. If you plan to travel overseas, it's best to get familiar with these taboos before you start touring local sites. The following are some examples.
Singapore
You can get fined for a lot of things in Singapore, including feeding birds, spitting, urinating in public, smoking in public, not flushing a public toilet after you use it, and eating or drinking on buses or trains.
Japan
You're not supposed to wear your shoes in someone’s house, but you're not supposed to take your shoes off outside the house either. Instead, there's a small area inside the door called a “genkan” which is where your shoes should go. If you're still not sure where that is, pay attention to what other people do and do the same.
France
French people don't like it when you talk about money. It's OK if you say that you want to quit a job because you are paid little money, but you should never say the exact amount. Money is a “dirty” topic in France.
1.When traveling abroad, we can’t ________.
A.relax and take a break from normal daily life
B.follow what other people do and do the same
C.be always free to do whatever we like
D.tour the local sites and give salutes
2.The underlined word “taboos” means something you must________doing.
A.enjoy B.avoid C.finish D.keep
3.________is considered to be proper.
A.Eating or drinking on buses or trains in Singapore
B.Wearing your shoes in your Japanese friend’s house
C.Talking about how much money you can make in France
D.Not smoking, spitting or feeding birds in public in Singapore
4.You can read this passage in (a)n________.
A.advertisement B.poster C.novel D.magazine
It was Daniel’s first trip to Disney World, and he couldn’t wait to get there.
At first he played all the silly car games with his sister Emily and parents. But there were still hours to get there. “Are we...?”
“No, Daniel,” his father said. “Please try to be patient.”
“Yeah, but this is so boring!” Daniel said.
“It's more than boring,” Emily said.
“You want to hear something about torture（折磨）?” Dad asked. “When I was your age, your grandparents took your aunt Jan and me to travel. About halfway there, we got a flat tire(轮胎). Luckily, we had a spare one, but it took a long time to change it because Grandpa dropped the lug nuts(螺母) and they rolled into the highway. He had to flag down a police car to close the right lane(车道) , so he could get the lug nuts.”
Daniel laughed, “Grandpa must have been really mad!”
“Oh, he wasn’t happy, but it got worse,” Dad said. “About fifty miles later, the engine died. Grandpa tried to fix it but he failed. So he had to walk three miles to get to a pay phone and call for help.”
“What happened next?” Daniel asked.
“We had to pay for a cheap hotel room for the night while the car was in a car repair shop being fixed.” Both Daniel and Emily laughed.
1.How did Emily like the trip to Disney World at first?
A.She thought it was wonderful. B.She thought it was comfortable.
C.She thought it was dangerous. D.She thought it was very boring.
2.Why did Daniel's grandpa have to flag down a police car to close the right lane?
A.Because he thought a policeman could help him to change the tire.
B.Because he wanted to get the lug nuts and change the tire himself.
C.Because he wanted another driver driving on the highway to help him.
D.Because he thought he could drive the police car to Disney World.
3.Who most probably succeeded in fixing the engine at last?
A.Daniel’s grandpa. B.Someone in the cheap hotel.
C.Daniel's father. D.Someone in the car repair shop.
4.How did Daniel feel when he was listening to his father’s story?
A.Bored. B.Interested. C.Sad. D.Hopeless.
Everyone knows that animals can sense natural disasters well before they happen. There are red ants __________ their homes before earthquakes. And there are monkeys moving to higher ground before tsunamis(海啸). Animals can predict the daily __________too. But how? Few people know. Now thanks to an ancient _________, we can get some of that wisdom.
The book says a lot of animals have the__________to predict the weather.__________them the cat appears to be the most powerful. So for those who have a cat at home, you can have a__________to see if the book is right or wrong. If you__________that your cat keeps sneezing, it's not a sign of being sick. It may be telling you that rain is on the way. There is another way to tell you the __________thing---your pet is spending a lot of time cleaning its head behind the ears.
When your cat starts to lie on its back for a longer time, get ready for a snowy day. The weather is about to turn for the__________and that there may just be a storm on the way. Your cat can even predict the__________of the wind after a rainstorm. Will it blow from south or north? Just see which side of face it is cleaning.
1.A.decorating B.building C.leaving
2.A.weather B.activity C.habit
3.A.report B.book C.genius
4.A.secret B.interest C.power
5.A.Between B.With C.Among
6.A.plan B.test C.solution
7.A.notice B.look C.search
8.A.different B.same C.difficult
9.A.better B.still C.worse
10.A.temperature B.level C.direction
—Why was Mrs. Li taken to the police station?
—Because she________stealing a lot of things from her neighbor.
A.treated herself to B.tricked into C.was accused of
