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  3. Anybody who doesn’t know much about nanotechnology should【B1】 ________ geckos. These are the lizards that are probably the worl

Anybody who doesn’t know much about nanotechnology should【B1】 ________ geckos. These are the lizards that are probably the worl

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问题     Anybody who doesn’t know much about nanotechnology should【B1】 ________  geckos. These are the lizards that are probably the world’s best climbers. Watching them climb upside down on a horizontal pane of glass, you realize that spiderman should really have been called geckoman. These guys outclimb spiders any day.
    With perfect【B2】 ________  they can hang from a single toe, and they do so by pure adhesion, not by sticking a toe in a hole or by【B3】 ________  it round something they can grip. With all the toes on the glass scientists【B4】 ________  that if the rest of the body were strong enough it could take the weight of a 100kg person【B5】 ________  below it. Although each toe is【B6】 ________  with a tiny hook-like claw at the end, these are of no use on the glass. What keeps them up there is the amazing structure of the skin of the toe.
    Seen under the microscope each toe has around two million tiny hairs on its underside. Under the higher【B7】 ________  of an electron microscope the end of each of these hairs is seen to【B8】 ________  into hundreds of even tinier nano-hairs, which scientists have called spatulae. These hairs are so small that they are able to establish contact with the molecular structure of the surface the gecko is walking on. With that near-perfect contact the hairs are stuck to the surface by forces called van der Waals forces. The molecules on the feet and on the surface have areas of slight positive or negative【B9】 ________  that attract each other like mini magnets when they get really close.
    Scientists have been working for over 15 years now to try to【B10】 ________  the secrets of the stickiness of gecko toes and find a way to【B11】 ________  reproduce the same structure of nano-hairs. The【B12】 ________  at the moment is that if any material can be shaped into nano-hairs they will have the same【B13】 ________  as those on gecko toes, so scientists are looking for a (n) alternative material with which to【B14】 ________  the stickiest synthetic surface ever.
    This is one example of research in the field now known as nanotechnology. In this field, the technology being created can be【B15】 ________  in a few nanometres (one nanometre is a millionth of a millimetre). Interest in developing technology at this level was largely inspired by Richard Feynman at the beginning of the 1960’s, but the "nano" catchphrase was【B16】 ________  in the 1990’s by Dr. Eric Drexler, who【B17】 ________  scientists on through a series of speeches and a book entitled " Engines of Creation; The Coming Era of Nanotechnology".
    The scientists working on the geckos【B18】 ________  an enormously wide range of possible applications for the kind of adhesive nanotechnology that they will develop. The one that will make the biggest splash in the media will be the gloves and the boots that will allow rock-climbers to take their sport to【B19】 ________  undreamed of heights. And the technology could also be used in surgery to keep the edges of wounds together without the need for stitches. There will also be a huge potential in the manufacturing sector to stick millions of 【B20】 ________  together tighter than ever before without glues or screws.
【B19】
选项 A、thereby
B、hitherto
C、whatsoever
D、henceforth
答案B
解析 逻辑关系题。选项的意思分别为[A]“因此，由此”；[B]“迄今，至今”；[C] “无论什么，丝毫”；[D]“从此以后”。本句说的是，“手套和靴子这些装备将使攀岩者能够爬到 ________ 做梦也想不到的高度”，将选项带入句子，发现只有[B]语义合适。
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