A Train Floating On Air
A train that floats on air? It's not magic―it's magnets (磁).And it's close to reality.
In Virginia USA the fall of 2002, a train with no wheels traveled on air and carried college students across their campus.In Japan, a whisper-quiet railway engine hovered and raced at 350 miles per hour using magnets and electricity as the power.And in China, a magnet train line linked Shanghai with nearby Pudong Airport.
These trains use magnetic levitation (懸浮) technology, “maglev” for short. They use the same rules as the magnets you pick up at home or school: opposite poles of magnets attract each other, and like poles repel each other.
How does it work?
Powerful magnets on the bottom of the train repel magnets on the track, which is actually just a magnet-filled guiding way. With a magnetic field of sufficient force, the train will go hovering on air, which seemed impossible to us in the past.
When an electrical current is sent through the track, the train moves. Turn the current backwards and the train slows down.
Maglev doesn't rely on the friction (摩擦力) of wheels on track, so it can climb a much steeper hill than a traditional train. And it can travel easily in snow and ice, something that could bring normal trains to a screaming stop.    
【小題1】This passage is about __________.

A．maglevB．magnetsC．levitationD．electricity
【小題2】 Which of the following is a repelling action?
 
A．B．C．D．
【小題3】What can we learn from the text?
A．A magnet-filled guiding way is formed inside a maglev train.
B．Instead of electricity, magnets are used as the power of a maglev.
C．Maglev trains can climb hills with the help of magnetwheels.
D．Electric currents decide the movements of a maglev train.
【小題4】 What is the difference between a maglev train and an ordinary train?
A．A maglev train can climb mountains without power while an ordinary one can’t.
B．A maglev train can travel in college campus while an ordinary train is not allowed.
C．Travelling without a track, a maglev train is safer and smoother than an ordinary one.
D．Floating on a track, a maglev train is faster, quieter than an ordinary railway train.


【小題1】A
【小題2】B
【小題3】D
【小題4】D

解析

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科目：高中英語(yǔ) 來(lái)源： 題型：閱讀理解

How do you define diplomacy（外交）? For the group Physicians for Peace（PEP），diplomacy is all about taking medical education and care to places where they are needed most．PEP brings together medical volunteers from different cultures and opposing sides of conflicts．Its message is “bring peace and international friendships through medicine”．

PEP is based in the American state of Virginia．Doctor Charles Horton，a plastic surgeon（整形外科醫(yī)生）known for his humanitarian work，established the group in the 1980s．

More than 500 teams of doctors，dentists，nurses and other health-care workers have gone to nearly 60 countries．Some programs have lasted for years．For example，PEP has had a program to treat burnt victims in Nicaragua since 1992．In Africa，the group is active in Liberia，Senegal，Mall and Malawi．And，in January，PEP will launch a class in pediatrics（兒科學(xué)）and general surgery in Eritrea．Thirteen medical students will learn about treating children and performing operations．In the Philippines，PEP is helping to provide eye care to people who have never had their eyes examined before．The group is also helping to fit replacement arms and legs for people who have had limbs amputated．

Charity Navigator，a service that rates nonprofit organizations，gives PEP its top rating．Health care providers from the US donate their time and pay their own travel costs．The group had fl budget last year of $35 million，most of which was the value of donated medical supplies．

According to Ron Sconyers，the CEO of PEP，the group goes only where it is invited．He says it receives more requests for assistance than it can meet，but works、hard not to turn anyone down．

1．According to the passage，the activities of PEP focus on _________．

A．developing good medicine for the world

B．offering medical education and care to the needed area

C．persuading countries to live in peace

D．directing diplomacy in conflicting areas

2．In paragraph 3，the underlined word “amputated” can be best replaced by “_________”．

A．examined             B．recovered             C．operated                 D．removed

3．We can learn from the passage that _________．

A．no Americans turn to PEP for help            B．Sconyers is always ready to help others

C．PEP is a nonprofit group                             D．Horton must work abroad

4．Which of the following is TRUE about PEP，according to the passage?

A．It has brought medical education to Nicaragua．

B．It will train medical students in Eritrea next year．

C．Donations to it mainly come from the US．

D．$35 million in cash was donated to it last year．

5．The best title for this passage would be _________．

A．Group Works to Build Peace Through Medicine

B．Charles Horton Sets Up Physicians for Peace

C．Charity Navigator Honors a Medical Group

D．The Poor Benefit from Physicians for Peace

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