The Issue of Package
Maybe everyone has such an experience that you have to unwrap several layers of packaging when you enjoy a piece of candy. But this overuse of wrapping is not confined to luxuries. It is becoming increasingly difficult to buy anything that is not done up in beautiful wrapping.
The package itself is of no interest to the shopper, who usually throws it away immediately. So why is it done? Some of it, like the cellophane on meat, is necessary, but most of the rest is simply competitive selling. This is absurd. Packaging is using up scarce energy and resources and messing up the environment.
Recycling is already happening with milk bottles which are returned to the dairies, washed out,and refilled. But both glass and paper are being threatened by the growing use of plastic. More dairies are experimenting with plastic bottles.
The trouble with plastic is that it does not rot. Some environmentalists argue that the only solution to the problem of ever increasing plastic containers is to do away with plastic altogether in the shops, a suggestion unacceptable to many manufacturers who say there is no alternative to their handy plastic packs.
It is evident that more research is needed into the recovery and reuse of various materials and into the cost of collecting and recycling containers as opposed to producing new ones. Unnecessary packaging, intended to be used just once, and make things look better so more people will buy them, is clearly becoming increasingly absurd. But it is not so much a question of doing away with packaging as using it sensibly. What is needed now is a more advanced approach to using scarce resources for what is, after all, a relatively unimportant function.
31. "This overuse of wrapping is not confined to luxuries. " (Line 2, Paragraph 1) means __________.
A. more wrapping is needed for ordinary products
B. more wrapping is used for luxuries than for ordinary products
C. too much wrapping is used for both luxury and ordinary products
D. the wrapping used for luxury products is unnecessary
32. Packaging is important to manufacturers because __________.
A. it is easy to use it again
B. shoppers are interested in beautiful packaging
C. they want to attract more shoppers
D. packaged things will not go rotten
33. According to the passage, dairies are __________.
A. experimenting with the use of paper bottles
B. giving up the use of glass bottles
C. increasing the use of plastic bottles
D. re-using their paper containers
34. Some environmentalists think that __________.
A. plastic packaging should be made more convenient
B. no alternative can be found to plastic packaging
C. too much plastic is wasted
D. shops should stop using plastic containers
35. The author thinks that
A. packing is actually useless and could be ignored
B.people will soon stop using packaging altogether
C.enough research has been done into recycling
D.it is better to produce new materials than to re—tlSe old ones
Backpacks are convenient. They can hold your books, your lunch, and a change of clothes leaving your hands free to do other things. Someday, if you don't mind carrying a heavy load, your backpacks might also power your MP3 player, keep your cell phone running, and maybe even light your way home.
Lawrence C. Rome and his colleagues from the University of Pennsylvania in Philadelphia and the Marine Biological Laboratory in Woods Hole, Mass. have invented a backpack thatmakes electricity from energy produced while its wearer walks. In military actions search-and-rescue operations and scientific field studies, people rely increasingly on cellphones global positioning system (GPS) receivers,night-vision goggles, and other battery powered devices to get around and do their work. The backpack's electricity-generating feature could dramatically reduce the amount of a wearer's load now devoted to spare batteries, report Rome and his colleagues in the Sept.9 science.
The backpack's electricity-creating powers depend on springs used to hang a cloth pack from its metal frame. The frame sits against the wearer's back, and the whole pack moves up and down as the person walks. A gear mechanism converts vertical movements of the pack to rotary motions of an electrical generator, producing up to 7.4 watts.
Unexpectedly, tests showed that wearers of the new backpack alter their gaits in response to the pack's oscillations, so that they carry loads more comfortably and with less effort than they do ordinary backpacks. Because of that surprising advantage, Rome plans to commercialize both electric and non-electric versions of the backpack.
The backpack could be especially useful for soldiers, scientists, mountaineers, and emergency workers who typically carry heavy backpacks. For the rest of us, power-generating backpacks could make it possible to walk, play video games, watch TV, and listen to music, all at the same time. Electricity-generating packs aren't on the market yet, but if you do get one eventually just make sure to look both ways before crossing the street!
36. Backpacks are convenient because __________.
A o they can be verylarge
B. they can hold as many things as you want to carry
C. your handsare freed to do other things
Do you do not have to carry things withyou
37. What is the most important feature of the backpack invented byLawrence C.Romeand his colleagues?
A. It produces electricity forelectronic devices while the wearer walks.
B. It can be used as cellphones, GPS in the military actions or field studies.
C. It is small andconvenient.
D. It is light and easy to carry.
38. The word "'springs" in Paragraph 3 means __________.
A. a small stream of water flowing naturally from theearth
B. the season of the year, occurring between winter and summer
C. the act or an instance of jumping or leaping
D. a length of metal woundaround, which returns to its original shape afterbeing pushed
39. According to Paragraph 4, what does Rome plan to do?
A. To make the backpackmore comfortable for the wearer.
B. To put the backpack on the market.
C. To test the advantage of the backpack.
D. To promote the backpack in anewspaper or on television.
40. What is implied in "if you do get oneeventually, just make sure to look bothways before crossing the street!"?
A. You will be too excited to watch the traffic.
B. Enjoyingelectronic devices while walking may invite traffic accidents.
C. It is notpossible for you to get such a backpack.
D. It is wise of you to have such abackpack.
Scientists can't yet make an invisibility cloak like the one that Harry Potter uses. But, for the first time, they've constructed a simple cloaking device that makes itself and something placed inside it invisible to microwaves.
When a person "sees" an object, his or her eye senses many different waves of visible light as they bounce off the object. The eye and brain then work together to organize the sensations and reconstruct the object's original shape. So, to make an object invisible, scientists have to keep waves from bouncing off it. And they have to make sure the object casts no shadow. Otherwise, the absence of reflected light on one side would give the object away.
Invisibility isn't possible yet with waves of light that the human eye can see. But it is now possible with microwaves. Like visible light, microwaves are a form of radiant energy. They are part of the electromagnetic spectrum, which also includes radio waves, infrared light, ultravioletmys, X rays, and gamma rays. The wave lengths of microwaves are shorter than those of radio waves but longer than those of visible light.
The scientists' new "invisibility device" is the size of a drink coaster and shaped likearing. The ring is made of a special material with unusual ability. When microwaves strike thering, very few bounce off it. Instead, they pass through the ring, which bends the waves all the way around until they reach the opposite side. The waves then return to their original paths.
To a detector set up to receive microwaves on the other side of the ring, it looks as if the waves never changed their paths as if there were no object in the way! So, the ring is effectively invisible.
When the researchers put a small copper loop inside the ring, it, too, is nearly invisible.
However, the cloaking device and anything inside it do cast a pale shadow. And the device works only for microwaves, not for visible light or any kind of electromagnetic radiation. So, Harry Potter's invisibility cloak doesn't have any real competition yet.
41. Harry Potter is mentioned in the passage, because scientists __________.
A. can now make an invisible cloak of the same kind as he uses
B. try to make an invisible cloak of the same kind as he uses
C. try to invent a device similar in idea to the invisible cloak he uses
D. know that it is possible to make an invisible cloak of the same kind
42. What is true of microwaves?
A. Their wavelengths are shorter than those of visible light.
B. Their wavelengths are longer than those of visible light.
C. They are different from visible light as they are a kind of radiant energy.
D. They are visible to the human eye.
43. What is NOT true of the invisibility device?
A. It is made of a special material with unusual ability.
B. Microwaves bounce off it when they strike it.
C. Microwaves pass through it when they strike it.
D. It bends the microwaves all the way around until they reach the opposite side.
44. What does the word "coaster" mean in the passage?
A. A disk or plate placed under a drinking glass to protect a table top.
B. A vessel engaged in coastal trade.
C. A roller coaster.
D. A resident of a coastal area.
45. Harry Potter's invisibility cloak doesn't have any real competition yet, because __________.
A. scientists have not found out how his cloak works
B. the cloaking device is a total failure
C. the cloaking device works only for microwaves
D. the cloaking device works only for visible light
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