题目内容

It is always hard for a small fish to live in a big pond．Pluto's recent departure(离开)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 neighbourhood around its orbit(轨道)．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 Plates status started in 1992．After an advanced telescope was sent into space, astronomers started to 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．

1．  The main purpose of the text is to ______.

A．prove to the readers that size matters  

B．tell readers about a big change of the planets

C．explain the classical theory of planets

D．inform us of science textbooks being updated

2．We can infer from the text that______.

   A．eight planets make up the solar system.

   B．it has been hard for scientists to define a “planet”

   C．Mars is very hot and you can’t go near it

   D．Pluto shares the same orbit with Neptune

3．Scientists argued about Pluto’s status for a long time because______.

   A．Pluto was first discovered in 1930

   B．the family of planets is too big

   C．Pluto is located beyond Neptune

   D．many dwarf planets, like Pluto, were found

4．The reason for Pluto’s departure is that______.

   A．Pluto does not fit the definition of a “planet”

   B．Pluto cannot compete with other planets

   C．Pluto is attracted by Neptune’s gravity

   D．other objects of its size have been discovered

5．The best title of the text is _____.

   A．an unexpected result                         B．Eight planets

   C．Goodbye Pluto                              D．New Scientific Definition

BBDAC

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C
A 17-year-old boy, caught sending text messages in class, was recently sent to the vice principal's office．The vice principal, Steve Gallagher, told the boy he needed to focus on the teach- er, not his cellphone．The boy listened politely and nodded, and that's when Mr．Gallagher noticed the student's fingers moving on his lap．He was texting while being scolded for texting．"It was a subconscious act," says Mr．Gallagher, who took the phone away．"Young people today are con-nected socially from the moment they open their eyes in the moming until they close their eyes at night． It's compulsive．"
A study this year by psychology students at Covenant College in Lookout Mountain, Ga．, found that the more time young people spend on Facebook, the more likely they are to have lower grades and weaker study habits． Heavy Facebook users show signs of being more sociable, but they are alsomore likely to be anxious, hostile or depressed．
Almost a quarter of today's teens check Facebook more than 10 times a day, according to a2009 survey by Common Sense Media, a nonprofit group that monitors media's impact on families．Will these young people get rid of this habit once they enter the work force, or will employers cometo see texting and 'social-network checking' as accepted parts of the workday? Think bac．k．Whentoday's older workers were in their 20s, they might have taken a break on the job to call friends andmake after-work plans．In those earlier eras, companies discouraged non-business-related calls, and someone who made personal calls all day risked being fired． It was impossible to imagine the con-stant back-and-forth texting that defines interactions among young people today．Educators are alsobeing asked by parents, students and educational strategists to reconsider their rules．"In past gen-erations, students got in trouble for passing notes in class．Now students are good at texting withtheir phones stiU in their pockets," says 40-year-old Mr．Gallagher, the vice principal,  ”and they're able to communicate with someone one floor down and three rows over．Students are just fun-amentally different today．They will take suspensions rather than give up their phones．"
66．The underlined word“a subconscious act" in the first paragraph refers to an act______
A．on purpose                      B．without realization
C．in secret                       D．with care
67．Young people addicted to the use of Facebook______．
A．are good at dealing with the social relationships and concentrate on their study
B．have high spirits and positive attitudes towards their life and work
C．have been influenced mentally in the aspects of behaviors and habits
D．are always in bad mood and have poor performance in every respect
68．Through the situation of today's older workers in their 20s, it can be inferred that______．
A．the employers will not accept young people's sending text messages
B．a cellphone is a must for today's older workers instead of young people
C．the employers prefer older workers to young people
D．the employers will find it hard to control the interaction among young people
69． Mr． Gallagher reminds us that the students in the past and those today______．
A．like to break rules and have the same means of sending messages
B．are alwa)-s the big problem for the educators and their parents
C．like sending text messages but those today do it in a more secret and skillful way  
D．cannot live without a ceUphone
70．What's the best title of the passage?
A．Teenagers and CeLl．phones         B．Teenagers' Texting Addiction
C．Employers and Teenagers              D．Teenagers' Education    

 

       A 17-year-old boy, caught sending text messages in class, was recently sent to the vice principal's office．The vice principal, Steve Gallagher, told the boy he needed to focus on the teach- er, not his cellphone．The boy listened politely and nodded, and that's when Mr．Gallagher noticed the student's fingers moving on his lap．He was texting while being scolded for texting．"It was a subconscious act," says Mr．Gallagher, who took the phone away．"Young people today are con-nected socially from the moment they open their eyes in the moming until they close their eyes at night．It's compulsive．"

       A study this year by psychology students at Covenant College in Lookout Mountain, Ga．, found that the more time young people spend on Facebook, the more likely they are to have lower grades and weaker study habits．Heavy Facebook users show signs of being more sociable, but they are alsomore likely to be anxious, hostile or depressed．

      Almost a quarter of today's teens check Facebook more than 10 times a day, according to a2009 survey by Common Sense Media, a nonprofit group that monitors media's impact on families．Will these young people get rid of this habit once they enter the work force, or will employers cometo see texting and 'social-network checking' as accepted parts of the workday? Think bac．k．Whentoday's older workers were in their 20s, they might have taken a break on the job to call friends andmake after-work plans．In those earlier eras, companies discouraged non-business-related calls, and someone who made personal calls all day risked being fired．It was impossible to imagine the con-stant back-and-forth texting that defines interactions among young people today．Educators are alsobeing asked by parents, students and educational strategists to reconsider their rules．"In past gen-erations, students got in trouble for passing notes in class．Now students are good at texting withtheir phones stiU in their pockets," says 40-year-old Mr．Gallagher, the vice principal,  ”and they're able to communicate with someone one floor down and three rows over．Students are just fun-amentally different today．They will take suspensions rather than give up their phones．"

1.The underlined word“a subconscious act" in the first paragraph refers to an act

       A．on purpose                              B．without realization

       C．in secret                               D．with care

2.Young people addicted to the use of Facebook                ．

       A．are good at dealing with the social relationships and concentrate on their study

       B．have high spirits and positive attitudes towards their life and work

       C．have been influenced mentally in the aspects of behaviors and habits

       D．are always in bad mood and have poor performance in every respect

3.Through the situation of today's older workers in their 20s, it can be inferred that        ．

       A．the employers will not accept young people's sending text messages

       B．a cellphone is a must for today's older workers instead of young people

       C．the employers prefer older workers to young people

       D．the employers will find it hard to control the interaction among young people

4.Mr．Gallagher reminds us that the students in the past and ．those today            ．

       A．like to break rules and have the same means of sending messages

       B．are alwa）-s the big problem for the educators and their parents

       C．like sending text messages but those today do it in a more secret and skillful way

       D．cannot live without a ceUphone

5.What's the best title of the passage?

       A．Teenagers and CeLl．Phones

     B．Teenagers' Texting Addiction

       C．Employers and Teenagers

       D．Teenagers' Education

 

C

A 17-year-old boy, caught sending text messages in class, was recently sent to the vice principal's office．The vice principal, Steve Gallagher, told the boy he needed to focus on the teach- er, not his cellphone．The boy listened politely and nodded, and that's when Mr．Gallagher noticed the student's fingers moving on his lap．He was texting while being scolded for texting．"It was a subconscious act," says Mr．Gallagher, who took the phone away．"Young people today are con-nected socially from the moment they open their eyes in the moming until they close their eyes at night． It's compulsive．"

A study this year by psychology students at Covenant College in Lookout Mountain, Ga．, found that the more time young people spend on Facebook, the more likely they are to have lower grades and weaker study habits． Heavy Facebook users show signs of being more sociable, but they are alsomore likely to be anxious, hostile or depressed．

Almost a quarter of today's teens check Facebook more than 10 times a day, according to a2009 survey by Common Sense Media, a nonprofit group that monitors media's impact on families．Will these young people get rid of this habit once they enter the work force, or will employers cometo see texting and 'social-network checking' as accepted parts of the workday? Think bac．k．Whentoday's older workers were in their 20s, they might have taken a break on the job to call friends andmake after-work plans．In those earlier eras, companies discouraged non-business-related calls, and someone who made personal calls all day risked being fired． It was impossible to imagine the con-stant back-and-forth texting that defines interactions among young people today．Educators are alsobeing asked by parents, students and educational strategists to reconsider their rules．"In past gen-erations, students got in trouble for passing notes in class．Now students are good at texting withtheir phones stiU in their pockets," says 40-year-old Mr．Gallagher, the vice principal,  ”and they're able to communicate with someone one floor down and three rows over．Students are just fun-amentally different today．They will take suspensions rather than give up their phones．"

66．The underlined word“a subconscious act" in the first paragraph refers to an act______

A．on purpose                       B．without realization

C．in secret                        D．with care

67．Young people addicted to the use of Facebook______．

A．are good at dealing with the social relationships and concentrate on their study

B．have high spirits and positive attitudes towards their life and work

C．have been influenced mentally in the aspects of behaviors and habits

D．are always in bad mood and have poor performance in every respect

68．Through the situation of today's older workers in their 20s, it can be inferred that______．

       A．the employers will not accept young people's sending text messages

       B．a cellphone is a must for today's older workers instead of young people

       C．the employers prefer older workers to young people

       D．the employers will find it hard to control the interaction among young people

69． Mr． Gallagher reminds us that the students in the past and those today______．

A．like to break rules and have the same means of sending messages

B．are alwa)-s the big problem for the educators and their parents

C．like sending text messages but those today do it in a more secret and skillful way  

       D．cannot live without a ceUphone

70．What's the best title of the passage?

A．Teenagers and CeLl．phones           B．Teenagers' Texting Addiction

C．Employers and Teenagers               D．Teenagers' Education    

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