试题与答案

直流电动机降低电枢电压调速时,转速只能从额定转速()。A、往下降B、开始反转C、往上

题型:单项选择题

题目:

直流电动机降低电枢电压调速时,转速只能从额定转速()。

A、往下降

B、开始反转

C、往上升

D、升高一倍

答案:

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题型:阅读理解

By 2012,the world may need to cope with as many as 50 million people who have fled their homeland,not for political or economic reasons but because the environment has been so badly changed that it cannot support life. The statement has been released by the United Nations to mark UN Disaster Reduction Day.

More people are made homeless by environmental disasters than by war,according to the research by the Red Cross. That reality is proved by the earthquake in Pakistan.

The widely publicized disaster has brought aid from the global community,according to Janos Bogardi,director of the United Nations University Institute for Environment and Human Security. “If we can move swiftly in and give them a new start where they are,then they may stay in the area. Otherwise,they become environmental refugees. Environmental­related migrations are most acute in Sub­Saharan Africa,but they also affect millions of people in Asia and India. Meanwhile,the United States is witnessing increased pressure from victims of mismanaged and worsening soil and water conditions in Mexico and Latin America.” he says. Janos Bogardi says these refugees suffer from the impact of gradual environmental change—global warming,sea level rise,air and water pollution and more intense storms,floods and droughts that degrade the land. This is a slow process,but unfortunately a process that is very difficult to go backwards once final damage is done.

Janos Bogardi says they are calling on the global community to recognize the serious situation of environmental refugees and to work together to lessen the impact of environmental disaster.

小题1:What may be the best title of the passage?

A.50 Million environmental refugees by 2010

B.Environmental refugees—an international problem

C.The cause of environmental disasters

D.Global aid pouring in小题2:Janos Bogardi’s attitude towards solving the problem is that of being ________.

A.constructive       

B.compromising

C.controversial

D.conservative小题3:According to the passage,the following are the main reasons for migrations except ________.

A.earthquake

B.water conditions

C.global community

D.worsening soil小题4:What is implied in the passage?

A.People all over the world have realized the impact of environmental disasters on refugees.

B.It is time for us to take some measures to solve the problem of environmental refugees.

C.The damaged soil can recover soon if people take care of it.

D.It is good for people to go elsewhere to make a living.

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