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  Imagine the battery on your mobile phone has run out.You can't make any calls for help and no one can contact you.You are all alone-well, not quite.Just reach into your pocket and take out a piece of sugar.Put it into the battery, wait a minute and you're back on the phone.

  Thanks to a couple of American scientists, this situation could become real.Swadesh Chaudhuri and Derek Lovley have invented the “bacteria(微生物) battery”-powered by bacteria that eats sugar and turns it into electricity.

  “This is a special organism(有机体),”Lovley said.“You can harvest enough electricity to power a cell phone battery for about four days from a spoonful of sugar.”

  In the past, bacteria batteries have been expensive and not long-lasting.But this battery uses more efficient bacteria that can turn 80 percent of sugar into electrical energy.This is 30 percent more than similar batteries can manage.The bacteria battery could become as small as a household battery.It's also cheap and stable, as sugar can be taken from waste and crops.

  But the sugar to electricity process is slow:it could take weeks for the bacteria to digest a cup of sugar.And it produces “greenhouse” gases which pollute the environment.The scientists understand there is a lot more work to be done.“It is still young, ”said Lovley.“Where we are now is where solar power(太阳能)was 20 or 30 years ago.”

  But he believes the battery could be used in scientific equipment at the bottom of the ocean.Other ideas include using sugar in the blood to run medical devices in the human body, and taking sugar from animal waste to provide energy to power homes in rural areas.

(1)

The scene described in the first paragraph is used to show ________.

[  ]

A.

humans can use sugar on our mobile phones

B.

people can't contact anyone without mobile phones

C.

people might use sugar on a mobile phone when necessary in future

D.

sugar is widely used on mobile phones

(2)

The “bacteria battery” invented by Swadesh Chaudhuri and Derek Lovley ________.

[  ]

A.

uses nothing to produce power

B.

proved useless

C.

gets power by chemical reaction

D.

is thought little of in scientific fields

(3)

The writer ________.

[  ]

A.

thinks highly of the bacteria battery

B.

has been using the bacteria battery for a long time

C.

has been engaged in the study of bacteria battery as well

D.

doubts whether the bacteria battery can become as small as a household batterry

(4)

The underlined sentence suggests ________.

[  ]

A.

the study of the bacteria battery needs 20 or 30 years to catch up with that of solar power

B.

the studies of the bacteria battery and solar power are both young

C.

20 or 30 years ago the study of solar power was young, just like that of the bacteria battery now

D.

the study of bacteria battery needs a long time to be equal to the level of solar power about 20 or 30 years ago

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