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　　Rescue Platform

　　In the aftermath of the terrorist attacks on the World Trade Center, security experts are trying to develop new ways of rescuing people from burning skyscrapers. One _______(51) is a platform capable of flying vertically and hovering in the air _______ (52)a helicopter. The platform would rise up and down alongside a skyscraper and pick up people _______ (53) in high stories.

　　The idea for the vertical takeoff platform was hatched(策劃) more than ten years ago by a Russian aerospace engineer, David Metreveli, who has since moved to Israel. Metreveli's design, _______(54) the Eagle, calls for two jet engines that_______(55) four large horizontal propellers. The spinning of the propellers _______(56) the necessary lift, or upward force, to raise the platform. The more _______(57)is supplied to the propellers, the higher the platform _______(58). Moving the platform sideways involves _______(59) differing amounts of power to each propeller.

　　Helicopters are now used in some _______(60) to get people out of burning buildings. Escape baskets slung from them dangle beside the building for people to climb into. _______(61), the baskets cannot reach every floor of a building_______ (62)the ropes from which they hang become unstable _______(63) a certain length.

　　So far, Metreveli has built a small-scale model of the Eagle to _______(64)his idea. In the wake of September 11,he has been able to secure enough funding to start building a larger,4-meter by 4-meter prototype, _______(65)he calls the Eaglet.

　　51. A idea B skill C building D improvement

　　52. A silks B unlike C like D likely

　　53. A B trapped C climbed D raised

　　54. A linked B called C equaled D described

　　55. A change B move C turn D shut

　　56. A sends B keeps C opens D generates

　　57. A power B sense C feature D model

　　58. A stays B rises C starts D runs

　　59. A reducing B comparing C developing D applying

　　60. A kinds B cases C stories D products

　　61. A Unfortunately B Uncertainly C Unimportantly D Unexpectedly

　　62. A before B because C until D however

　　63. A beyond B under C off D on

　　64. A tell B test C discuss D report

　　65. A who B which C where D what

　　標準答案： ACBBCDABDBABABB