题目内容
（请给出正确答案）
The world's pollution problems would be less serious if ______.
A．fewer people moved from countryside to the cities
B．more people moved from countryside to the cities
C．industry developed less fast
D．many people moved to the cities without the development of industry
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更多“The world's pollution problems…”相关的问题
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B.s.replace(6，10，“World”)
C.s=“World”
D.s=replace(“java”，“World”)
It can be concluded that ______.
A．raising the world's temperature only a few degrees would not do much harm to life on earth
B．lowering the world's temperature merely a few degrees would lead many major farming areas to disaster
C．almost no temperature variations have occurred over the past decade
D．the world's temperature will remain constant in the years to come
Without the artist's work, the public might not______.
A．understand the world better
B．notice the shapes and colors that express his experience
C．know those shapes and colors
D．feel comfortable and at ease
The best title for the text is______.
A．WTO — another name for GATT
B．WTO — an international service organization
C．WTO — one of the world's strongest economic organizations
D．WTO — one of the world's most powerful economic organization
A.at least
B.at best
C.at most
D.at worst
A.suffering
B.stamina
C.intelligence
D.ability
A.come off
B.come around
C.come up
D.come through
A、three months
B、three-month-old
C、three months old
D、three-months-old
--Never thought to meet you here. -- ______ .
A．So did Ⅰ
B．It's a small world
C．I didn't so
D．Glad to meet you
A．Travelers cleared up rubbish on mountains.
B．Children planted trees.
C．Government officials made speeches in public to encourage people to do something for the earth.
D．Artists and musicians gave shows to support the environmental group's work.
将英语短文译为中文
3 Self-Powered Nanotech (10分)
Nanosize machines need still tinier power plants
By Zhong Lin Wang
The watchmaker in the 1920s who devised the self-winding wristwatch was on to a great idea: mechanically harvesting energy from the wearer’s moving arm and putting it to work rewinding the watch spring.
Today we are beginning to create extremely small energy harvesters that can supply electrical power to the tiny world of nanoscale devices, where things are measured in billionths of a meter. We call these power plants nanogenerators. The ability to make power on a minuscule scale allows us to think of implantable biosensors that can continuously monitor a patient’s blood glucose level, or autonomous strain sensors for structures such as bridges, or environmental sensors for detecting toxins — all running without the need for replacement batteries. Energy sources are desperately needed for nanorobotics, microelectromechanical systems (MEMS), homeland security and even portable personal electronics. It is hard to imagine all the uses such infinitesimal generators may eventually find.
In Brief
★Nanotechnology has huge potential — but those minuscule devices will need a power source that is better than a battery.
★ Waste energy, in the form. of vibrations or even the human pulse, could provide sufficient power to run such tiny gadgets.
★ Arrays of piezoelectric nanowires could capture and transmit that waste energy to nanodevices.
★ Medical devices will likely be a major application. A pacemaker’s battery could be charged so it would not need replacing, or implanted wireless nanosensors could monitor blood glucose for diabetics.
