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[单项选择]
Conserve Electricity

You probably don’t even realize it, but an energy thief is inside your home at this very moment. This thief is silent and unseen, and he’s picking your pocket. His name is "standby power." Standby power is the name given to the electricity used to power electrical appliances and devices even when they are turned off. But how can this be Isn’t an appliance "off" when you switch it off Not necessarily.
Many electronic devices consume electricity 24 hours a day just to stay warmed up for whenever you decide to use them. "Instant on" TV sets are one example. Whether you watch TV seven hours a day or not at all, the TV is always partially on, staying ready to flicker to life the moment you turn on its switch.
Other devices that consume power constantly are those that have external or internal clocks: microwave ovens, computers, VCRs, DVD players, and cable TV and satellite TV boxes. Energy experts estimate that a
A. Supportive
B. Critical
C. Indifferent
D. Worrie

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[不定项选择题]共用题干第三篇

Archive Gallery: The Best of Bionics（仿生学）

Humans might be the most highly-evolved species on the planet,but most animals possess skills we can
only dream of having.Imagine how much electricity we could save if we could see in the dark the way cats
do. Imagine leaping from tree to tree like a monkey.Giraffes（长颈鹿）,which are otherwise calm and good-
natured,sleep only 4.6 hours a day.
We realized a long,long time ago that nature provides the best blueprint（蓝图）for invention.We've
borrowed canals from beavers（河狸）and reflectors from cat's eyes.Although the words "bionics" became
popular only after the 1960s,history shows that nature has always provided ideas on solving everyday prob-
lems. Our archives（档案）don't go back to the time of Leonardo da Vinci and his bird-like flying machines,
but we can take you to the late 19th century,where we applied those same principles for building our first
practical airplanes.
To prepare for their flight at Kitty Hawk,the Wright brothers studied the movements of pigeons to figure
out how they stayed high up when they were heavier than air. Their success inspired scores of successors to
improve on the airplane by studying various aspects of nature,One of Orville Wright’、pupils caught and
stuffed seagulls to examine their wingspan.Meanwhile,two French inventors examined spinning sycamore（美
国梧桐）seeds in an effort to apply those same motions,reversed,to a helicopter.
Some examples are more obvious than others.The outside of the airplane designed by the Wright
brothers looks like a minimalistic（简单抽象艺术）structure. On the other hand , Barney Connett ' s fish
submarine（潜水艇）actually looks like a fish.
Some bio-inspired concepts have yet to be invented.In the 1960s，the US Army commissioned several
university professors to conduct research on the motor skills of animals in hope of applying those same abili-
ties to tanks. Tanks that run like horses or jump like grasshoppers（蚂昨）一sounds shocking,doesn't it?
But imagine how life would change if we could achieve that. Which of the following is true about the research carried out by the US Army?
A.It has changed our life.
B.It has cost a large sum of money.
C.It has improved the abilities of tanks.
D.It has not succeeded yet.