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        2017職稱英語《理工類C級》完形填空??嘉恼略?

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            Singing Alarms Could Save the Blind
            If you cannot see, you may not be able to1 find your way out of a burning building — and that could be fatal. A company in Leeds could change all that2____1____ directional sound alarms capable of guiding you to the exit.
            Sound Alert, a company____2____ the University of Leeds, is installing the alarms in a residential home for____3____ people in Sommerset and a resource centre for the blind in Cumbria.____4____ produce a wide range of frequencies that enable the brain to determine where the____5____ is coining from.
            Deborah Withington of Sound Alert says that the alarms use most of the frequencies that can be____6____ by humans. “It is a burst of white noise____7____ people say sounds like static on the radio,” she says. “Its life-saving potential is great.”
            She conducted an experiment in which people were filmed by thermal-imaging cameras trying to find their way out of3 a large____8____ room. It____9____ them nearly four minutes to find the door____10____ a sound alarm, but only 15 seconds with one.
            Withington studies how the brain____11____ sounds at the university. She says that the____12____ of a wide band of frequencies can be pinpointed more easily than the source of a narrow band. Alarms____13____ the same concept have already been installed on emergency vehicles.
            The alarms will also include rising or falling frequencies to indicate whether people should go up____14____ down stairs. They were____15____ with the aid of a large grant from British Nuclear Fuels.
            詞匯:
            directional / d?'rek??nl; da?- / adj.定向的
            exit / 'eks?t / n.出口
            install / ?n'st?:l / v.安裝
            residential / rez?'den??l / adj.居住的
            static / 'st?t?k / n.靜電噪聲
            potential / p?'ten??l / n.潛力
            thermal-imaging熱效應成像
            pinpoint / 'p?np??nt / v.精確地確定
            concept / 'k?nsept / n.概念,觀念
            emergency / ?'m??d??ns? / n.緊急情況
            grant / grɑ?nt / n.授予物,準許