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Germs（细菌）on Banknotes
People in different countries use different types of money:yuan in China,pesos in Mexico,pounds in the United Kingdom,dollars in the United States,Australia and New Zeal-and. They may use different currencies,but these countries,and probably all countries,still have one thing in______(1):germs on the banknotes.
Scientists have been studying the germs on money for well over 100 years. At the turn of the 20th______(2),some researchers began to suspect that germs living on money could spread disease.
Most studies of germy money have looked at the germs on the currency______(3)one country. In a new study,Frank Vriesekoop and other researchers compared the germ populations found on bills of different______(4).
Vriesekoop is a microbiologist at the University of Ballarat in Australia. He led the stud-y,which compared the germ populations found on money______(5)from 10 nations. The scientists studied 1,280 banknotes in total;all came from places where people buy food,like supermarkets,street vendors and cafes,______(6)those businesses often rely on cash.
Overall,the Australian dollars hosted the fewest live bacteria一no more than 10 per square centimeter. Chinese yuan had the______(7）about 100 per square centimeter. Most of the germs on money probably would not cause harm.
What we call“paper money”_________(8)isn't made from paper. The U. S. dollar,for ex- ample,is printed on fabric that is mostly cotton. Different countries may use different______(9)to print their money. Some of the currencies studied by Vriesekoop and his team,such as the American dollar,were made from cotton. Others were made from polymers.
The three______(10)with the lowest numbers of bacteria were all printed on poly-mers. They included the Australian dollar,the New Zealand dollar and some Mexican pesos.
The______(11)currencies were printed on fabric made mostly of cotton. Fewer germs lived on the polymer notes. This______(12)suggests that germs have a harder time staying alive on polymer surfaces. Scientists need to do more studies to understand______(13)germs live on, mon-ey—and whether or not we need to be concerned. Vriesekoop is now starting a study that will______(14)the amounts of time bacteria can stay alive on different types of bills.
Whatever Vriesekoop finds,the fact remains:Paper money______(15)germs. We should wash our hands after touching it;After all,you never know where your money's been. Or what's living on it.
6._________
A: because
B: though
C: so
D: when
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Dark Forces Dominate Universe
The earth,moon,sun and all visible stars in the sky make up less than one percent of
the universe.Almost all the rest is dark matter and dark energy,unknown forces that
_______(1)astronomers.
Observations in recent years have changed the basic_______(2)of how the
universe evolved and have indicated how little is known about the major forces and
substances that_______(3)our world.
Astronomers now know that luminous（发光的）matter一stars , planets and hot gas一
accounts_______(4)only about 0.4 percent of the universe.Non-luminous
components , such as black holes and intergalactic（星系间的）gas,_______(5)
up 3.6 percent.The rest is either dark matter,about 23 percent,or dark energy,about
73 percent.
Dark matter,sometimes_______(6)"cold dark matter,"has been known for some time.Only recently have researchers come to understand the key role it_______ (7)in the formation of stars,planets and even people.
"We_______(8)our very existence to dark matter,"said physicist Paul
Steinhardt and a co-author of a review on dark matter which_______(9)not long ago
in the journal Science.
"Dark matter dominated the structure_______(10)in the early universe,"
Steinhardt said."For the first few billion years dark matter contained most of the mass of the
universe. You can think of ordinary matter_______(11)a froth（泡沫）of an ocean
of dark matter. The dark matter clumps（结成块）and the ordinary matter falls into it. That
_______(12) to the formation of the stars and galaxies（星系）."
Without dark matter,"there would be virtually no structures in the universe,"
The nature of dark matter is_______(13).It cannot be seen or detected
directly. Astronomers know it is there because of its_______(14) on celestial（天体
的）objects that can be seen and measured.
But the most dominating force of all in the universe is called dark energy,a recently
________(15)power that astronomers say is causing the galaxies in the universe to
separate at a faster and faster speed.
_________(10)
A:element
B:shape
C:formation
D:power
Dark Forces Dominate Universe
The earth,moon,sun and all visible stars in the sky make up less than one percent of
the universe.Almost all the rest is dark matter and dark energy,unknown forces that
_______(1)astronomers.
Observations in recent years have changed the basic_______(2)of how the
universe evolved and have indicated how little is known about the major forces and
substances that_______(3)our world.
Astronomers now know that luminous（发光的）matter一stars , planets and hot gas一
accounts_______(4)only about 0.4 percent of the universe.Non-luminous
components , such as black holes and intergalactic（星系间的）gas,_______(5)
up 3.6 percent.The rest is either dark matter,about 23 percent,or dark energy,about
73 percent.
Dark matter,sometimes_______(6)"cold dark matter,"has been known for some time.Only recently have researchers come to understand the key role it_______ (7)in the formation of stars,planets and even people.
"We_______(8)our very existence to dark matter,"said physicist Paul
Steinhardt and a co-author of a review on dark matter which_______(9)not long ago
in the journal Science.
"Dark matter dominated the structure_______(10)in the early universe,"
Steinhardt said."For the first few billion years dark matter contained most of the mass of the
universe. You can think of ordinary matter_______(11)a froth（泡沫）of an ocean
of dark matter. The dark matter clumps（结成块）and the ordinary matter falls into it. That
_______(12) to the formation of the stars and galaxies（星系）."
Without dark matter,"there would be virtually no structures in the universe,"
The nature of dark matter is_______(13).It cannot be seen or detected
directly. Astronomers know it is there because of its_______(14) on celestial（天体
的）objects that can be seen and measured.
But the most dominating force of all in the universe is called dark energy,a recently
________(15)power that astronomers say is causing the galaxies in the universe to
separate at a faster and faster speed.
_________(10)
A:element
B:shape
C:formation
D:power
In judging our work you should take into consideration the fact that we have been very busy recently.
A:thought
B:account
C:mind
D:brain
A:thought
B:account
C:mind
D:brain
共用题干
Smoking can Increase Depressive Symptoms in Teens
While some teenagers may use cigarettes to "self-medicate"（自我治疗）against the blues（忧郁）,sci-
entists at the University of Toronto and the University of Montreal have found that smoking may actually
______________
(51)depressive symptoms in some teens.
"This observational study is one of the few to examine the perceived ______________(52)benefits of
smoking among teens,"says lead researcher Michael Chaiton,a research associate at the Ontario Tobacco
Research Unit of the University of Toronto."_______________(53)cigarettes may appear to have self-medicating
effects or to improve mood,in the long_______________(54)we found that teens who started to smoke reported
higher depressive symptoms."
As part of the study,some 662 high school teenagers completed up to 20 questionnaires about their use
of cigarettes to ______________
(55)mood.Secondary schools were selected to provide a mix of French and
English participants,urban and rural schools,and schools ______________(56)in high,moderate and low so-
cioeconomic neighbourhoods.
Participants were divided into three
______________ (57):never smokers;smokers who did not use ciga-
rettes to self-medicate,improve mood or physical
______________ (58);smokers who used cigarettes to self-
medicate.Depressive symptoms were measured using a scale that asked how often participants felt too tired
to do things;had
______________ (59)going to sleep or staying asleep;felt unhappy,sad,or depressed;felt
hopeless about the future;felt anxious or tense;and worried too much about things.
" Smokers who used cigarettes as mood
______________( 60 ) had higher risks of elevated（提升）depres-
sive symptoms______________ (61)teens who had never smoked,"says co-researcher Jennifer O'Loughlin,a
professor at the University of Montreal Department of Social and Preventive Medicine."Our study found that
teen smokers who reported emotional benefits from smoking are_______________(62)higher risk of developing
depressive symptoms."
The______________ (63)between depression and'smoking exists______________(64)among teens that use
cigarettes to feel better."It's ______________(65)to emphasize that depressive symptom scores were higher
among teenagers who reported emotional benefits from smoking after they began to smoke,"says Dr. Chaiton.
_________(57)
A:groups
B:sets
C:species
D:versions
Smoking can Increase Depressive Symptoms in Teens
While some teenagers may use cigarettes to "self-medicate"（自我治疗）against the blues（忧郁）,sci-
entists at the University of Toronto and the University of Montreal have found that smoking may actually
______________
(51)depressive symptoms in some teens.
"This observational study is one of the few to examine the perceived ______________(52)benefits of
smoking among teens,"says lead researcher Michael Chaiton,a research associate at the Ontario Tobacco
Research Unit of the University of Toronto."_______________(53)cigarettes may appear to have self-medicating
effects or to improve mood,in the long_______________(54)we found that teens who started to smoke reported
higher depressive symptoms."
As part of the study,some 662 high school teenagers completed up to 20 questionnaires about their use
of cigarettes to ______________
(55)mood.Secondary schools were selected to provide a mix of French and
English participants,urban and rural schools,and schools ______________(56)in high,moderate and low so-
cioeconomic neighbourhoods.
Participants were divided into three
______________ (57):never smokers;smokers who did not use ciga-
rettes to self-medicate,improve mood or physical
______________ (58);smokers who used cigarettes to self-
medicate.Depressive symptoms were measured using a scale that asked how often participants felt too tired
to do things;had
______________ (59)going to sleep or staying asleep;felt unhappy,sad,or depressed;felt
hopeless about the future;felt anxious or tense;and worried too much about things.
" Smokers who used cigarettes as mood
______________( 60 ) had higher risks of elevated（提升）depres-
sive symptoms______________ (61)teens who had never smoked,"says co-researcher Jennifer O'Loughlin,a
professor at the University of Montreal Department of Social and Preventive Medicine."Our study found that
teen smokers who reported emotional benefits from smoking are_______________(62)higher risk of developing
depressive symptoms."
The______________ (63)between depression and'smoking exists______________(64)among teens that use
cigarettes to feel better."It's ______________(65)to emphasize that depressive symptom scores were higher
among teenagers who reported emotional benefits from smoking after they began to smoke,"says Dr. Chaiton.
_________(57)
A:groups
B:sets
C:species
D:versions
共用题干
第一篇
Walking to Exercise the Brain
Do you think sitting and studying all the time will improve your grades?Think again.Getting some exer-
cise may help,too.
New research with old people suggests that taking regular walks helps them pay attention better than if
they didn't exercise.
Previous research had shown that mice learn,remember,and pay attention better after a few weeks of
working out on a running wheel.Mice that exercise have greater blood flow to the brain than those who don't.
Their brain cells also make more connections.
Neuroscientists（神经科学家）from the University of Illinois at Urbana Champaign wanted to find out if
the same thing is true for people.First,they measured the physical fitness of 41 adults,ages 58 to 77,after
each person walked 1 mile.Then,participants looked at arrows on a computer screen and had to use computer
keys to show which way one particular arrow was pointing.
Adults who were physically fit were faster at the arrow task,and their answers were just as accurate as
their less-fit peers,the researchers found.The fitter participants also had more blood flow to a part of their
brain responsible for paying attention and making decisions.
In a second study , 15 elderly people who completed a 6-month aerobic-training（有氧运动）course were
faster at attention tasks compared with 14 seniors who just did stretching and toning exercises（韵律操）for
the same amount of time.
So,even going for a walk every 2 or 3 days for just 10 to 45 minutes can help.That should be good news
for the elderly.
The effects of exercising on the brains of younger people haven't been studied yet. Still,it can't hurt to
take occasional breaks and go for a walk or run around with friends.Whatever you do,though,don't try to
read and walk at the same time.You could end up hurting yourself!
The first study on 41 elderly people found______________.
A:the less-fit participants did arrow tasks faster
B:the fitter participants did arrow tasks faster
C:the less-fit participants gave more accurate answers
D:the fitter participants gave more accurate answers
第一篇
Walking to Exercise the Brain
Do you think sitting and studying all the time will improve your grades?Think again.Getting some exer-
cise may help,too.
New research with old people suggests that taking regular walks helps them pay attention better than if
they didn't exercise.
Previous research had shown that mice learn,remember,and pay attention better after a few weeks of
working out on a running wheel.Mice that exercise have greater blood flow to the brain than those who don't.
Their brain cells also make more connections.
Neuroscientists（神经科学家）from the University of Illinois at Urbana Champaign wanted to find out if
the same thing is true for people.First,they measured the physical fitness of 41 adults,ages 58 to 77,after
each person walked 1 mile.Then,participants looked at arrows on a computer screen and had to use computer
keys to show which way one particular arrow was pointing.
Adults who were physically fit were faster at the arrow task,and their answers were just as accurate as
their less-fit peers,the researchers found.The fitter participants also had more blood flow to a part of their
brain responsible for paying attention and making decisions.
In a second study , 15 elderly people who completed a 6-month aerobic-training（有氧运动）course were
faster at attention tasks compared with 14 seniors who just did stretching and toning exercises（韵律操）for
the same amount of time.
So,even going for a walk every 2 or 3 days for just 10 to 45 minutes can help.That should be good news
for the elderly.
The effects of exercising on the brains of younger people haven't been studied yet. Still,it can't hurt to
take occasional breaks and go for a walk or run around with friends.Whatever you do,though,don't try to
read and walk at the same time.You could end up hurting yourself!
The first study on 41 elderly people found______________.
A:the less-fit participants did arrow tasks faster
B:the fitter participants did arrow tasks faster
C:the less-fit participants gave more accurate answers
D:the fitter participants gave more accurate answers
共用题干
The iPad
1 The iPad is a tablet computer（平板电脑）designed and developed by Apple. It is par-ticularly marketed as a platform for audio and visual media such as books,periodicals（期刊）,movies,music,and games,as well as web content. At about 1 .5 pounds(680 grams), its size and weight are between those of most contemporary smartphones and laptop comput-ers.Apple released the iPad in April 2010,and sold 3 million of the devices in 80 days.
2 The iPad runs the same operating system as iPod Touch and iPhone. It can run its own applications as well as ones developed for iPhone. Without modification,it will only run pro-grams approved by Apple and distributed via its online store.
3 Like iPhone and iPod Touch,the iPad is controlled by a multitouch display一a break from most previous tablet computers, which uses a pressure-triggered stylus（触控笔）.The iPad uses a Wi-Fi data connection to browse（浏览）the Internet, load and stream media, and install software. Some models also have a 3G wireless data connection which can connect to GSM 3G data networks. The devices is managed and synchronized（同步）by iTunes on a per-sonal computer via USB cable.
4 An iPad has different features and applications one can use to execute different and in-teresting things. There are lots of iPad applications that the owner can use to enhance the way they communicate. Some of these are how to use social networking sites and other online options.One of the most common uses is for e-mail services. iPad applications like Markdown Mail allow the adoption of specific and particular options. They enable the owner to personal-ize their email accounts.
5 While the iPad is mostly used by consumers it also has been taken up by business us-ers. Some companies are adopting iPads in their business offices by distributing or making available iPads to employees.Examples of uses in the workplace include lawyers responding to clients,medical professionals accessing health records during patient exams,and manag-ers approving employee requests.A survey by Frost Sullivan shows that iPad usage in work-places is linked to the goals of increased employees productivity,reduced paperwork,and in-creased revenue.
Paragraph 2______
A: Online Stores
B: Differences from iPhone
C: Display and Data Connection
D: Business Usage
E: Features and Applications
F: Operating System
The iPad
1 The iPad is a tablet computer（平板电脑）designed and developed by Apple. It is par-ticularly marketed as a platform for audio and visual media such as books,periodicals（期刊）,movies,music,and games,as well as web content. At about 1 .5 pounds(680 grams), its size and weight are between those of most contemporary smartphones and laptop comput-ers.Apple released the iPad in April 2010,and sold 3 million of the devices in 80 days.
2 The iPad runs the same operating system as iPod Touch and iPhone. It can run its own applications as well as ones developed for iPhone. Without modification,it will only run pro-grams approved by Apple and distributed via its online store.
3 Like iPhone and iPod Touch,the iPad is controlled by a multitouch display一a break from most previous tablet computers, which uses a pressure-triggered stylus（触控笔）.The iPad uses a Wi-Fi data connection to browse（浏览）the Internet, load and stream media, and install software. Some models also have a 3G wireless data connection which can connect to GSM 3G data networks. The devices is managed and synchronized（同步）by iTunes on a per-sonal computer via USB cable.
4 An iPad has different features and applications one can use to execute different and in-teresting things. There are lots of iPad applications that the owner can use to enhance the way they communicate. Some of these are how to use social networking sites and other online options.One of the most common uses is for e-mail services. iPad applications like Markdown Mail allow the adoption of specific and particular options. They enable the owner to personal-ize their email accounts.
5 While the iPad is mostly used by consumers it also has been taken up by business us-ers. Some companies are adopting iPads in their business offices by distributing or making available iPads to employees.Examples of uses in the workplace include lawyers responding to clients,medical professionals accessing health records during patient exams,and manag-ers approving employee requests.A survey by Frost Sullivan shows that iPad usage in work-places is linked to the goals of increased employees productivity,reduced paperwork,and in-creased revenue.
Paragraph 2______
A: Online Stores
B: Differences from iPhone
C: Display and Data Connection
D: Business Usage
E: Features and Applications
F: Operating System