Invisibility Ring
Scientists cant yet make an invisibility cloak1 like the one that Harry Potter2 uses.But，for the first time，theyve constructed a simple cloaking device that makes itself and somethingplaced inside it invisible to microwaves.
Invisibility isnt possible yet with waves of light that the human eye can see.But it is nowpossible with microwaves.Like visible light，microwaves are a form of radiant energy.Theyare part of the electromagnetic spectrum，which also includes radio waves，infrared light，ultraviolet rays，X rays，and gamma rays.The wavelengths of microwaves are shorter thanthose of radio waves but longer than those of visible light.
To a detector set up to receive microwaves on the other side of the ring，it looks as if thewaves never changed their paths as if there were no object in the way! So，the ring is effectively invisible.
词汇：
cloak斗篷，披风 infraredadj.红外线的5maikrEuweivp
reconstructv.重建 gamma ray 伽马射线5reidjEnt5weivleNWp
electromagneticadj.电磁的coastern.托盘，垫子
1.Harry Potter is mentioned in the passage，because scientists
Btry to make an invisible cloak of the same kind as he uses.
Dknow that it is possible to make an invisible cloak of the same kind.
ATheir wavelengths are shorter than those of visible light.
CThey are different from visible light as they are a kind of radiant energy.
3.What is NOT true of the invisibility device?
BMicrowaves bounce off it when they strike it.
DIt bends the microwaves all the way around until they reach the opposite
4.What does the word coaster mean in the passage?
BA vessel engaged in coastal trade.
DA resident of a coastal area.
because
Bthe cloaking device is a total failure.
Dthe cloaking device works only for visible light.
C文章的第一段告诉我们，科学家还没有发明哈里波特使用的那种隐身衣，所以不能选 A;该段还告诉我们，科学家已制造了，一种装置，这种装置能使自身或置于其中的物体不被微波发现，所以C是正确选择，也就是说，科学家发明的隐形装置和哈里波特的隐身衣仅仅在概念上相同，这同时说明B和D是错误的选择。
B第四段第三句说，当微波到达装置表面时，very few bounce off。very few是几乎没有的意思，所以选择B。其他选择所述内容都可以很容易在该段中找到。
CA句在短文中没有提到;按文章的内容B不是正确的说法;文章最后一段说，And thedevice works only for microwaves，not forvisible light，所以C是正确选择