It is a mystery that has puzzled doctors for decades. But experts believe they have now finally solved the tricky question of why winter is notoriously known as the flu season.
According to a new research, the influenza virus coats itself in a protective fatty shield that is tough enough to resist cold temperatures. The butter-like material only melts when it hits the respiratory tract（呼吸道）, leaving the virus free to infect cells-- a process scientists say is like an M&M melting in the mouth.
However, in warmer outdoor temperatures, the protective coating melts before it reaches a person or an animal, killing the bacteria before they can infect someone. Joshua Zimmerberg, from the National Institute of Child Health and Human Development (NICHD), in the US, which led the study, said: “Like an M&M in your mouth, the protective covering melts when it enters the respiratory tract. It's only in this liquid period that the virus is able to enter a cell to infect it.”
In the past, scientists worked on theories that flu is more common in winter because people spend more time inside or the radiation from the sun in summer kills off germs. But no research successfully explained the spread of the disease.
Researchers have already claimed that the report, which is published in the journal Nature Chemical Biology, could lead to new ways to prevent and treat flu. “Now that we understand how the flu virus protects itself so that it can spread from person to person, we can work on ways to prevent it.”
Influenza and other respiratory viruses are spread in small drops broadcast by coughing, sneezing and talking and which can also settle onto surfaces, to be picked up on fingertips.
1. What can be the best title of the passage?
A. The mystery that has puzzled doctors for decades.    B. New ways to prevent and treat flu.
C. A discovery of how flu strikes in Winter.            D. Ways found to prevent flu.
2. Which of the following statements is NOT true?
A. Doctors have been trying hard to discover why flu strikes in winter.
B. In the past, scientists didn’t know how flu spreads.
C. It is possible that flu virus will no longer threaten humans in winter.
D. People get affected by flu because they spend much more time inside in winter.
3. Where should you insert the following paragraph into the passage?
Duane Alexander, the director of NICHD, said: “The study results open new avenues of research for thwarting (使…受挫)winter flu outbreaks.”
A. Between Paragraphs 1 and 2.     B. Between Paragraphs 3 and 4. 
C. Between Paragraphs 4 and 5.     D. Between the last two paragraphs.
4.In what process or order does flu occur?
a. The virus infects cells                 b. The influenza virus was born
c. The butter-like material melts           d. The virus hits respiratory tract
e. The virus coats itself in butter-like shield  f. The virus is free
A. a, c, d, e, b, f .     B. c, f, d, b, e, a.    C. b, e, d, c, f, a.    D. d, b, e, c, f, a.

It is a mystery that has puzzled doctors for decades. But experts believe they have now finally solved the tricky question of why winter is notoriously known as the flu season.

According to a new research, the influenza virus coats itself in a protective fatty shield that is tough enough to resist cold temperatures. The butter-like material only melts when it hits the respiratory tract（呼吸道）, leaving the virus free to infect cells-- a process scientists say is like an M&M melting in the mouth.

However, in warmer outdoor temperatures, the protective coating melts before it reaches a person or an animal, killing the bacteria before they can infect someone. Joshua Zimmerberg, from the National Institute of Child Health and Human Development (NICHD), in the US, which led the study, said: “Like an M&M in your mouth, the protective covering melts when it enters the respiratory tract. It's only in this liquid period that the virus is able to enter a cell to infect it.”

In the past, scientists worked on theories that flu is more common in winter because people spend more time inside or the radiation from the sun in summer kills off germs. But no research successfully explained the spread of the disease.

Researchers have already claimed that the report, which is published in the journal Nature Chemical Biology, could lead to new ways to prevent and treat flu. “Now that we understand how the flu virus protects itself so that it can spread from person to person, we can work on ways to prevent it.”

Influenza and other respiratory viruses are spread in small drops broadcast by coughing, sneezing and talking and which can also settle onto surfaces, to be picked up on fingertips.

1. What can be the best title of the passage?

  A. The mystery that has puzzled doctors for decades.    B. New ways to prevent and treat flu.

  C. A discovery of how flu strikes in Winter.            D. Ways found to prevent flu.

2. Which of the following statements is NOT true?

  A. Doctors have been trying hard to discover why flu strikes in winter.

  B. In the past, scientists didn’t know how flu spreads.

  C. It is possible that flu virus will no longer threaten humans in winter.

  D. People get affected by flu because they spend much more time inside in winter.

3. Where should you insert the following paragraph into the passage?

Duane Alexander, the director of NICHD, said: “The study results open new avenues of research for thwarting (使…受挫)winter flu outbreaks.”

  A. Between Paragraphs 1 and 2.     B. Between Paragraphs 3 and 4. 

  C. Between Paragraphs 4 and 5.     D. Between the last two paragraphs.

4.In what process or order does flu occur?

  a. The virus infects cells                 b. The influenza virus was born

  c. The butter-like material melts           d. The virus hits respiratory tract

  e. The virus coats itself in butter-like shield  f. The virus is free

  A. a, c, d, e, b, f .     B. c, f, d, b, e, a.    C. b, e, d, c, f, a.    D. d, b, e, c, f, a.

It is a mystery that has puzzled doctors for decades. But experts believe they have now finally solved the tricky question of why winter is notoriously known as the flu season.

According to a new research, the influenza virus coats itself in a protective fatty shield that is tough enough to resist cold temperatures. The butter-like material only melts when it hits the respiratory tract（呼吸道）, leaving the virus free to infect cells-- a process scientists say is like an M&M melting in the mouth.

However, in warmer outdoor temperatures, the protective coating melts before it reaches a person or an animal, killing the bacteria before they can infect someone. Joshua Zimmerberg, from the National Institute of Child Health and Human Development (NICHD), in the US, which led the study, said: “Like an M&M in your mouth, the protective covering melts when it enters the respiratory tract. It's only in this liquid period that the virus is able to enter a cell to infect it.”

In the past, scientists worked on theories that flu is more common in winter because people spend more time inside or the radiation from the sun in summer kills off germs. But no research successfully explained the spread of the disease.

Researchers have already claimed that the report, which is published in the journal Nature Chemical Biology, could lead to new ways to prevent and treat flu. “Now that we understand how the flu virus protects itself so that it can spread from person to person, we can work on ways to prevent it.”

Influenza and other respiratory viruses are spread in small drops broadcast by coughing, sneezing and talking and which can also settle onto surfaces, to be picked up on fingertips.

1. What can be the best title of the passage?

  A. The mystery that has puzzled doctors for decades.    B. New ways to prevent and treat flu.

  C. A discovery of how flu strikes in Winter.            D. Ways found to prevent flu.

2. Which of the following statements is NOT true?

  A. Doctors have been trying hard to discover why flu strikes in winter.

  B. In the past, scientists didn’t know how flu spreads.

  C. It is possible that flu virus will no longer threaten humans in winter.

  D. People get affected by flu because they spend much more time inside in winter.

3. Where should you insert the following paragraph into the passage?

Duane Alexander, the director of NICHD, said: “The study results open new avenues of research for thwarting (使…受挫)winter flu outbreaks.”

  A. Between Paragraphs 1 and 2.     B. Between Paragraphs 3 and 4. 

  C. Between Paragraphs 4 and 5.     D. Between the last two paragraphs.

4.In what process or order does flu occur?

  a. The virus infects cells                 b. The influenza virus was born

  c. The butter-like material melts           d. The virus hits respiratory tract

  e. The virus coats itself in butter-like shield  f. The virus is free

  A. a, c, d, e, b, f .     B. c, f, d, b, e, a.    C. b, e, d, c, f, a.    D. d, b, e, c, f, a.

It is always hard for a small fish to live in a big pond. Pluto's recent departure from the classical planet family clearly proves that size really matters.
Astronomers voted on August 24 to create the first scientific definition of the word planet, and Pluto obviously didn't make the cut. It turned out to be only a "dwarf planet" (矮行星). After weeks of heated debate, over 2,500 astronomers from 73 countries voted on the definition of a "planet" at a conference of the international Astronomical Union (IAU). According to the definition, a planet must have a clear neighborhood around its orbit. Pluto has widely been considered a planet since its discovery in 1930. Unfortunately, it has a special orbit which overlaps with Neptune's. It is all because, compared with Neptune, Pluto is very small. It is attracted by Neptune's gravity when the two planets get closer.
According to IAU, a "dwarf planet" should have an orbit around the Sun. It will not have a clear neighborhood around its orbit, and must not be a satellite. The new classification means that the science textbooks will have to be updated. The solar system is now made up of the eight "classical planets," together with a number of dwarf planets. The classical planets are: Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus and Neptune. The debate over Pluto's status started in 1992. After an advanced telescope was sent into space, astronomers started find a belt of objects, which lies beyond Neptune. The belt contains nearly 1,000 objects, including Pluto. As they continued the exploration, scientists recently discovered at least 41 dwarf planets at the edges of the solar system. There are at least two objects of a similar size to Pluto.
It seems that even if the IAU had kept Pluto's status as a planet, the classical theory of nine planets in the solar system would have had to be changed, but the other way around. More dwarf, planets of a similar size to Pluto would join the family of planets. Scientists will probably find many more dwarf planets.
【小题1】According to the passage, Pluto is          .

Human remains of ancient settlements will be reburied and lost to science under a law that threatens research into the history of humans in Britain, a group of leading archeologists (考古学家) says. In a letter addressed to the justice secretary, Ken Clarke, 40 archaeologists write of their “deep and widespread concern” about the issue. It centers on the law introduced by the Ministry of Justice in 2008 which requires all human remains unearthed in England and Wales to be reburied within two years, regardless of their age. The decision means scientists have too little time to study bones and other human remains of national and cultural significance.
“Your current requirement that all archaeologically unearthed human remains should be reburied, whether after a standard period of two years or a further special extension, is contrary to basic principles of archaeological and scientific research and of museum practice,” they write.
The law applies to any pieces of bone uncovered at around 400 dig sites, including the remains of 60 or so bodies found at Stonehenge in 2008 that date back to 3,000 BC. Archaeologists have been granted a temporary extension to give them more time, but eventuallly the bones will have to be returned to the ground.
The arrangements may result in the waste of future discoveries at sites such as Happisburgh in Norfolk, where digging is continuing after the discovery of stone tools made by early humans 950,000 years ago. If human remains were found at Happisburgh, they would be the oldest in northern Europe and the first indication of what this species was. Under the current practice of the law those remains would have to be reburied and effectively destroyed.
Before 2008, guidelines allowed for the proper preservation and study of bones of sufficient age and historical interest, while the Burial Act 1857 applied to more recent remains. The Ministry of Justice assured archaeologists two years ago that the law was temporary, but has so far failed to revise it.
Mike Parker Pearson, an archaeologist at Sheffield University, said: “Archaeologists have been extremely patient because we were led to believe the ministry was sorting out this problem, but we feel that we cannot wait any longer.”
The ministry has no guidelines on where or how remains should be reburied, or on what records should be kept.

1. 1.

   According to the passage, scientists are unhappy with the law mainly because ______.

   1. A.
      it is only a temporary measure on the human remains
   2. B.
      it is unreasonable and thus destructive to scientific research
   3. C.
      it was introduced by the government without their knowledge
   4. D.
      it is vague about where and how to rebury human remains
2. 2.

   Which of the following statements is true according to the passage?

   1. A.
      Temporary extension of two years will guarantee scientists enough time.
   2. B.
      Human remains of the oldest species were dug out at Happisburgh.
   3. C.
      Human remains will have to be reburied despite the extension of time.
   4. D.
      Scientists have been warned that the law can hardly be changed.
3. 3.

   What can be inferred about the British law governing human remains?

   1. A.
      The Ministry of Justice did not intend it to protect human remains.
   2. B.
      The Burial Act 1857 only applied to remains uncovered before 1857.
   3. C.
      The law on human remains hasn’t changed in recent decades.
   4. D.
      The Ministry of Justice has not done enough about the law.
4. 4.

   Which of the following might be the best title of the passage?

   1. A.
      New discoveries should be reburied, the government demands.
   2. B.
      Research time should be extended, scientists require.
   3. C.
      Law on human remains needs thorough discussion, authorities say.
   4. D.
      Law could bury ancient secrets for ever, archeologists warn.